Differences in myocardial velocity gradient measured throughout the cardiac cycle in patients with hypertrophic cardiomyopathy, athletes and patients with left ventricular hypertrophy due to hypertension

OBJECTIVES: We sought to compare the myocardial velocity gradient (MVG) measured across the left ventricular (LV) posterior wall during the cardiac cycle between patients with hypertrophic cardiomyopathy (HCM), athletes and patients with LV hypertrophy due to systemic hypertension and to determine whether it might be used to discriminate these groups. BACKGROUND: The MVG is a new ultrasound variable, based on the color Doppler technique, that quantifies the spatial distribution of transmyocardial velocities. METHODS: A cohort of 158 subjects was subdivided by age into two groups: Group I (mean [+/-SD] 30 +/- 7 years) and Group II (58 +/- 8 years). Within each group there were three categories of subjects: Group Ia consisted of patients with HCM (n = 25), Group Ib consisted of athletes (n = 21), and Group Ic consisted of normal subjects; Group IIa consisted of patients with HCM (n = 19), Group IIb consisted of hypertensive patients (n = 27), and Group IIc consisted of normal subjects (n = 33). RESULTS: The MVG (mean [+/-SD] s-1) measured in systole was lower (p < 0.01) in patients with HCM (Group Ia 3.2 +/- 1.1; Group IIa 2.9 +/- 1.2) compared with athletes (Group Ib 4.6 +/- 1.1), hypertensive patients (Group IIb 4.2 +/- 1.8) and normal subjects (Group Ic 4.4 +/- 0.8; Group IIc 4.8 +/- 0.8). In early diastole, the MVG was lower (p < 0.05) in patients with HCM (Group Ia 3.7 +/- 1.5; Group IIa 2.6 +/- 0.9) than in athletes (Group Ib 9.9 +/- 1.9) and normal subjects (Group Ic 9.2 +/- 2.0; Group IIc 3.6 +/- 1.5), but not hypertensive patients (Group IIb 3.3 +/- 1.3). In late diastole, the MVG in patients with HCM (Group Ia 1.3 +/- 0.8; Group IIa 1.4 +/- 0.8) was lower (p < 0.01) than that in hypertensive patients (Group IIb 4.3 +/- 1.7) and normal subjects (Group IIc 3.8 +/- 0.9). An MVG < or = 7 s-1, as a single diagnostic approach, differentiated accurately (0.96 positive and 0.94 negative predictive value) between patients with HCM and athletes when the measurements were taken during early diastole. CONCLUSIONS: In both age groups, the MVG was lower in both systole and diastole in patients with HCM than in athletes, hypertensive patients or normal subjects. The MVG measured in early diastole in a group of subjects 18 to 45 years old would appear to be an accurate variable used to discriminate between HCM and hypertrophy in athletes.     

Value of right ventricular ejection fraction in predicting short-term prognosis of patients with severe chronic heart failure

BACKGROUND: The prognosis of chronic heart failure has been studied extensively, but factors predicting short-term outcome in patients with severe chronic heart failure are still poorly defined, and the current indications for heart transplantation as a treatment for end-stage heart failure need on objective analysis. METHODS: Purpose of the study was to identify the determinants of short-term prognosis in a group of 142 consecutive ambulatory patients (mean age 49.8 +/- 11 years). Referred for heart transplantation because of severe chronic heart failure, the patients were admitted with left ventricular ejection fraction markedly depressed and had had symptoms in spite of an optimal standardized medical therapy for at least 1 month. Baseline clinical and instrumental evaluation included right-sided heart catheterization with a flow-directed multilumen thermodilution catheter, which enables determination of pressures, cardiac output, right ventricular volumes, and ejection fraction. RESULTS: Most patients were in New York Heart Association class III (61%) and IV (24%), and the hemodynamic profile was characterized by mean left ventricular ejection fraction of 20.2% +/- 6%, cardiac index of 2.13 +/- 0.6 l/min/m2, pulmonary capillary wedge pressure of 23.1 +/- 11 mm Hg, right atrial pressure of 7.9 +/- 6 mm Hg, right ventricular ejection fraction of 23.2% +/- 12.4%. During a mean follow-up of 11.1 +/- 9.4 months, 33 patients underwent transplantation (23.4%), 41 died (28.8%), and 68 were still alive (47.8%). There was a substantial overlap in left ventricular ejection fraction between patients divided on the basis of outcome, whereas right ventricular ejection fraction was significantly lower in patients who died or underwent transplantation. Cox multivariate analysis showed three independent prognostic variables: cause (p = 0.03), heart failure score (p = 0.001), and right ventricular ejection fraction (p = 0.000). Short-term survival (10 months) was significantly (p = 0.000) different in patients with > or = 24% or < 24% right ventricular ejection fraction. Statistical analysis identified right ventricular ejection fraction as the single variable to be highly correlated with an increased risk of early death. CONCLUSIONS: This study suggests that right ventricular function is a crucial determinant of short-term prognosis in severe chronic heart failure. Statistical analysis identified right ventricular ejection fraction, determined by thermodilution during right-sided heart catheterization, as the single most important predictor of short-term prognosis in a large cohort of patients who had symptoms in spite of a standardized, optimized, multipharmacologic treatment. The variable allows a useful risk stratification in patients with severe chronic heart failure and uniformly depressed left ventricular ejection fraction and provides guidance in the assessment of indications and timing for transplantation.     

Changes in right ventricular hemodynamic function by unilateral pulmonary arterial occlusion test

We performed unilateral pulmonary arterial occlusion test (UPAO) for the preoperative evaluation of lung function in patients undergoing lung resection. In this test, the main pulmonary artery of either side is occluded to simulate postoperative functional status. In order to evaluate the right ventricular hemodynamic function, we measured right ventricular ejection fraction (RVEF) and right ventricular end-diastolic volume index (RVEDVI) throughout UPAO by thermodilution method. We investigated the relationships between changes in right ventricular hemodynamic function and postoperative complications related to cardiac functions, namely arrhythmias or heart failure. Thirty-four patients without heart disease prior to lung resection were examined by UPAO, and RVEF and RVEDVI were measured. Analyses demonstrated that changes in RVEF were inversely correlated with changes in RVEDVI. In 6 cases, RVEDVI increased from control by over 20% during UPAO. All of these patients had postoperative cardiac complications. The hypothetical ventricular function curves showed a large increase in RVEDVI relative to right ventricular stroke work index (RVSWI), suggesting a decrease in right ventricular function. In conclusion, these results suggest that changes in RVEDVI during UPAO may predict postoperative cardiac complications in patients undergoing pulmonary resection.     

Effects of late percutaneous transluminal coronary angioplasty of an occluded infarct-related coronary artery on left ventricular function in patients with a recent (< 6 weeks) Q-wave acute myocardial infarction (Total Occlusion Post-Myocardial Infarction Intervention Study [TOMIIS]--a pilot study)

The effect of late percutaneous transluminal coronary angioplasty (PTCA) of an occluded infarct-related artery on left ventricular ejection fraction was studied in patients with a recent, first Q-wave myocardial infarction in a prospective, randomized study. Forty-four patients (31 men and 13 women, mean age 58 +/- 12 years) with an occluded infarct-related coronary artery were randomized to PTCA (n = 25) or no PTCA (n = 19). Patients received acetylsalicylic acid, a beta blocker and an angiotensin-converting enzyme inhibitor unless contraindicated. Left ventricular ejection fraction was determined at baseline and 4 months. Coronary angiography was repeated at 4 months. Baseline ejection fraction measured 20 +/- 12 days after myocardial infarction was 45 +/- 12% in both groups. PTCA was performed 21 +/- 13 days after the event. The primary PTCA success rate was 72%. One patient in each group died before angiographic follow-up, which was completed in 37 of the remaining 42 patients (88%; 21 with and 16 without PTCA). At 4 months, the infarct-related artery was patent in 43% of PTCA patients and in 19% of no PTCA patients (p = NS). Reocclusion occurred in 40% of patients after successful PTCA. Secondary analyses showed that the change in left ventricular ejection fraction was significantly greater in patients with a patent infarct-related artery (+9.4 +/- 6.2%) than in those with an occluded artery (+1.6 +/- 8.8%; p = 0.0096). Baseline ejection fraction also independently predicted improvement in left ventricular ejection fraction (p = 0.0001).(ABSTRACT TRUNCATED AT 250 WORDS)     

Pulmonary function following laparoscopic or conventional colorectal resection: a randomized controlled evaluation

BACKGROUND: Laparotomy causes a significant reduction of pulmonary function, and atelectasis and pneumonia occur after elective conventional colorectal resections. OBJECTIVE: To evaluate the hypothesis that pulmonary function is less restricted after laparoscopic than after conventional colorectal resection. DESIGN: A randomized clinical trial. SETTING: The surgical department of an academic medical center. PATIENTS: Sixty patients underwent laparoscopic (n = 30) or conventional (n = 30) resection of colorectal tumors. The 2 groups did not differ significantly in age, sex, localization or stage of tumor, or preoperative pulmonary function. MAIN OUTCOME MEASURES: Forced vital capacity, forced expiratory volume in 1 second, peak expiratory flow, mid-expiratory phase of forced expiratory flow, and oxygen saturation of arterial blood. RESULTS: The forced vital capacity (mean +/- SD values: conventional resection group, 1.73+/-0.60 L; laparoscopic surgery group, 2.59+/-1.11 L; P<.01) and the forced expiratory volume in 1 second (conventional resection group, 1.19+/-0.51 L/s; laparoscopic surgery group, 1.80+/-0.80 L/s; P<.01) were more profoundly suppressed in the patients having conventional resection than in those having laparoscopic surgery. Similar results were found for the peak expiratory flow (conventional resection group, 2.51+/-1.37 L/s; laparoscopic resection group, 3.60+/-2.22 L/s; P<.05) and the midexpiratory phase of forced expiratory flow (conventional resection group, 1.87+/-1.12 L/s; laparoscopic surgery group, 2.67+/-1.76 L/s; P<.05). The oxygen saturation of arterial blood, measured while the patients were breathing room air, was lower after conventional than after laparoscopic resections (P<.01). The recovery of the forced vital capacity and forced expiratory volume in 1 second to 80% of the preoperative value took longer in patients having conventional resection than in those having laparoscopic resection (P<.01). Pneumonia developed in 2 patients having conventional resection, but no pulmonary infection occurred in the laparoscopic resection group (P>.05). CONCLUSIONS: Pulmonary function is better preserved after laparoscopic than after conventional colorectal resection. Pulmonary complications may be reduced after laparoscopic resections because of the better postoperative pulmonary function.     

Antiplatelet glycoprotein autoantibodies in patients with autoimmune diseases with and without thrombocytopenia

The presence and specificity of antiplatelet autoantibodies in 32 patients with primary and 18 patients with secondary autoimmune thrombocytopenic purpura (AITP), as well as 11 non-thrombocytopenic patients with systemic autoimmune diseases, were studied. By means of the direct and indirect monoclonal antibody immobilization of platelet antigen (MAIPA) assay, antiplatelet autoantibodies were detected using monoclonal antibodies specific for platelet glycoproteins (GPs) Ib, IIb/IIIa, Ia/IIa, and IV. Serum antiplatelet autoantibodies were found in 18 of 32 primary AITP patients (56%), 6 of 18 secondary AITP patients (33%), and 5 of 11 nonthrombocytopenic patients (45%). Platelet-associated autoantibodies were detected in five of eight patients with primary (62%) and in four of eight patients with secondary AITP (50%) and in two of four patients without thrombocytopenia (50%). Multiple antibody reactivity, mainly against GPs IIb/IIIa and Ib and, in a few patients, against Ia/IIa, was found. Using MAIPA, platelet xylene eluates from 20 patients were also studied. Antiplatelet elutable autoantibodies were related to thrombocytopenia; autoantibodies against membrane GPs Ib and IIb/IIIa were demonstrable in 84 and 63% of eluates from patients with primary and secondary AITP, respectively, but not in eluates from nonthrombocytopenic patients. The presence of antiplatelet antibodies thus appears to be a common feature of many autoimmune diseases apart from the thrombocytopenia, but the (primary or secondary) etiology of the immune thrombocytopenia cannot be differentiated on the grounds of their specificity.     

Right ventricular function after aorto-coronary bypass surgery: with relation to the site of right coronary artery occlusion

Postoperative right ventricular function was evaluated serially by thermodilution techniques (REF-1, Edwards Laboratories) in patients who underwent aorto-coronary bypass surgery with uneventful postoperative recovery. The patients were divided into three groups depending on the location of critical stenosis of the right coronary artery. The stenosis was proximal to the right ventricular branch in group I (n = 13), distal to the right ventricular branch but proximal to the acute marginal branch in group II (n = 13) and distal to the acute marginal branch in group III (n = 11). Control (n = 20) consisted of the patients with no significant stenosis of the right coronary artery. Cardiac index, intracardiac pressures and amount of cathecolamin used during postoperative course showed no significant differences among the groups including control. With the use of cathecolamine after surgery, right ventricular ejection fraction (RVEF) rose and right ventricular volumes (RVEDV and RVESV) decreased in all the groups except for group I. These values in group I were unchanged. Thus, there were significant differences in RVEF, RVEDV and RVESV between group I and control. These results mean that right ventricular dysfunction may remain even long after occlusion of the proximal right coronary artery.     

Repair of left ventricular aneurysm: long-term results of linear repair versus endoaneurysmorrhaphy

BACKGROUND: Recently, endoaneurysomorrhaphy has been proposed as a more physiologic repair of postinfarction left ventricular aneurysm than is linear repair. There are only a few studies comparing the short-term and long-term results of the two techniques. METHODS: Clinical outcomes and echocardiographic measurements of left ventricular volume and sphericity in 27 patients who underwent endoaneurysmorrhaphy were compared with those in 20 patients who had linear repair. RESULTS: The two groups were matched with respect to age, gender, comorbid risk factors, functional class, urgency of the operation, and concomitant procedures. Preoperatively, left ventricular ejection fraction was lower in the endoaneurysmorrhaphy group (0.25 +/- 0.08 versus 0.30 +/- 0.09; p = 0.03). Follow-up was available in 44 patients (94%) and ranged from 2 to 86 months (mean, 41.0 +/- 26.5 months). Thirty-day operative mortality, perioperative complications, 5-year survival, and freedom from cardiac death were similar. Early postoperative percentage increase in left ventricular ejection fraction was greater after endoaneurysmorrhaphy (0.51 +/- 0.64 versus 0.18 +/- 0.48; p = 0.036). Long-term functional improvement was significantly better in the endoaneurysmorrhaphy group: At the time of last follow-up, 88% of patients were in New York Heart Association class I/II, compared with 53% after linear repair (p = 0.01). There were no measurable differences between the groups with respect to left ventricular ejection fraction (0.28 +/- 0.11 versus 0.27 +/- 0.11; p = 0.90), left ventricular volume (171.6 +/- 59.1 versus 169.9 +/- 54.4 mL; p = 0.94), and sphericity index (0.61 +/- 0.09 versus 0.61 +/- 0.12; p = 1.0). CONCLUSIONS: Despite having a similar effect on left ventricular geometry, endoaneurysmorrhaphy resulted in a greater increase in postoperative left ventricular ejection fraction and a substantially improved long-term clinical outcome.     

Comparison of the direct platelet immunofluorescence test (direct PIFT) with a modified direct monoclonal antibody-specific immobilization of platelet antigens (direct MAIPA) in detection of platelet-associated IgG

Glycoprotein (GP)-specific platelet-associated IgG (PA-IgG) may be demonstrable in autoimmune-mediated thrombocytopenia. We studied 159 consecutive patients with histories of thrombocytopenia by a modified direct monoclonal antibody-specific immobilization of platelet antigens (direct MAIPA) assay, which immobilizes GP IIb/ IIIa, GP Ib/IX and GP Ia/IIa simultaneously. This modification requires smaller quantities of platelets than standard measurements performed separately. PA-IgG was present in 84/159 (53%) patients, as shown by the direct platelet immunofluorescence test (PIFT) with flow cytometry as a reference. PA-IgG against GP IIb/IIIa and/or GP Ib/IX and/or GP Ia/IIa was noted in 46 patients (29%), of whom 93% (43/46)-were also PA-IgG positive. The amount of PA-IgG detected by PIFT correlated directly with that detected by direct MAIPA (r = 0.71; P < 0.001). Only three patients 12548 with negative direct PIFT had GP-specific PA-IgG. GPV-specific PA-IgG was detected in 13 (10%) of the 125 patients, in whom further studies could be performed. In the subgroup of patients with GP-specific PA-IgG, the median fluorescence intensities of direct PIFT were higher than in patients with no GP-specific PA-IgG (P < 0.001). Direct PIFT and direct MAIPA divided the patients into asymmetric subgroups. However, the relative roles of these tests in the diagnosis of autoimmune-mediated thrombocytopenia await further studies.     

Inhaled nitric oxide reduction in systolic pulmonary artery pressure is less in patients with decreased left ventricular ejection fraction

OBJECTIVE: To assess whether inhaled nitric oxide decreases pulmonary artery pressure in patients with depressed left ventricular ejection fraction. DESIGN: Randomized, blinded, crossover clinical trial. SETTING: Tertiary care university referral hospital. PATIENTS: Thirty-three patients with pulmonary hypertension and left ventricular dysfunction or valvular heart disease were recruited by convenience. INTERVENTIONS: Systolic pulmonary artery pressure was measured by Doppler echocardiography during randomized inhalation of either 20 ppm or 40 ppm nitric oxide in 30% oxygen as well as during control periods without nitric oxide. MAIN RESULTS: Systolic pulmonary artery pressure was significantly (P < 0.05) decreased with 20 ppm nitric oxide (53.4 +/- 13.9 mmHg) and 40 ppm nitric oxide (53.1 +/- 14.4 mmHg) compared with either initial control (55.8 +/- 15.3 mmHg) or terminal control (56.3 +/- 15.2 mmHg) values. The regression equation for the change in systolic pulmonary artery pressure (y) as predicted by the left ventricular ejection fraction (x) alone for 20 ppm nitric oxide was y = 13.8x-2.9; R2adj = 0.30, P < 0.0001. For 40 ppm nitric oxide alone, the regression equation was y = 16.3x-3.3; R2adj = 0.25, P < 0.0001. Left ventricular ejection fraction was the most explanatory independent variable in the multivariate equation for nitric oxide-induced change in systolic pulmonary artery pressure (R2 = 0.61, P = 0.0000). The change in systolic pulmonary artery pressure was -5.1 +/- 5.2 versus 0.8 +/- 4.9 mmHg (P < 0.0000) in patients with left ventricular ejection fractions greater than 0.25, and 0.25 or less, respectively. CONCLUSIONS: These data imply that in patients with left ventricular ejection fraction of 0.25 or less, nitric oxide may not decrease systolic pulmonary artery pressure. Nitric oxide inhalation may result in a paradoxical increase in systolic pulmonary artery pressure in patients with severely depressed left ventricular ejection fraction. This effect would significantly limit the therapeutic role of nitric oxide in patients with severe heart failure.     

Congestive heart failure in patients with valvular aortic stenosis. A clinical and echocardiographic Doppler study

The aim of this study was to evaluate echographically anatomic and functional features of the left ventricle in adult patients with valvular aortic stenosis according to the presence or absence of congestive heart failure and the level of ventricular performance. Fifty-six adult patients with moderate-to-severe aortic stenosis underwent echocardiographic Doppler examination in order to evaluate left ventricular mass and dimensions, systolic function and filling dynamics. Twenty-seven patients had no heart failure and were symptomatic for angina (5), syncope (4) or were symptom-free (group I); the other 29 had heart failure (group II): 16 with normal left ventricular systolic performance (fractional shortening > 25%, group IIa) and 13 with systolic dysfunction (fractional shortening < or = 25%, group IIb). Despite a similar left ventricular mass, compared to group IIa, group IIb showed a significant left ventricular dilatation (end-diastolic diameter: 61 +/- 6.5 vs. 45.5 +/- 6.1 mm, p < 0.001) and mild or no increase in wall thickness (11.5 +/- 1.6 vs. 14.9 +/- 2 mm, p < 0.001). Indices of left ventricular filling on Doppler transmitral flow were also significantly different between the two groups, with a higher early-to-late filling ratio and a shorter deceleration time of early filling in group IIb (2.8 +/- 1.9 vs. 1.2 +/- 0.85, p < 0.01, and 122 +/- 66 vs. 190 +/- 87 ms, p < 0.05, respectively), both indirectly indicating higher left atrial pressure. Finally, heart failure was generally more severe in group IIb patients. In some patients with aortic stenosis, symptoms of heart failure may be present despite a normal left ventricular systolic function and seem to depend on abnormalities of diastolic function. The presence of systolic or isolated diastolic dysfunction appears to be related to a different geometric adaptation of the left ventricle to chronic pressure overload.     

The dobutamine stress test with thallium-201 single-photon emission computed tomography and radionuclide angiography: postinfarction study

OBJECTIVES: The purpose of this study was to investigate left ventricular wall motion changes during dobutamine-induced myocardial ischemia. BACKGROUND: Dobutamine is increasingly used as a stress test. It has been assumed that high doses of the drug induce the same changes in contractility as physical exercise. However, some data suggest that ischemic myocardium can respond to dobutamine with an increase in contractility. METHODS: Sixty-three postinfarction patients twice underwent the dobutamine test (up to 40 micrograms/kg per min) within 1 to 2 days. Thallium-201 single-photon emission computed tomography (SPECT) and gated equilibrium radionuclide ventriculography were performed on each patient at rest and with dobutamine. Both global and regional ejection fractions were quantified. Sixty patients underwent coronary cineangiography within 1 week. The presence of redistribution was correlated with global and regional ejection fraction changes and with coronary lesions. RESULTS: Redistribution was present in 45 patients, and no change or a decrease in global or regional ejection fraction was detected in 22. In the entire group of patients global ejection fraction increased from 46 +/- 12% to 56 +/- 14%. The six patients with triple-vessel disease had a flat (-0.2 +/- 5%) ejection fraction response to dobutamine, whereas the remaining patients had an increase of 11 +/- 7% (p = 0.003). The regional ejection fraction of the hypokinetic area increased from 27 +/- 10% to 41 +/- 19%, showing no change or a decrease in 13 patients. The 44 patients with peri-infarct redistribution had a significantly higher increase in regional ejection fraction than those without redistribution (16.4 +/- 10% vs. 4.7 +/- 17%, p = 0.003). In the patients with peri-infarct redistribution, an inverse linear correlation was found between redistribution score and dobutamine-induced regional ejection fraction change (r = -0.44, p = 0.004). CONCLUSIONS: Mild to moderate dobutamine-induced peri-infarct ischemia is compatible with an increase in contractility, whereas severe ischemia induces worsening of wall motion.     

Right ventricular function in patients with dilated cardiomyopathy: assessment using krypton-81 m blood pool scintigraphy

The characteristics and pathogenesis of right ventricular dysfunction in 14 patients with dilated cardiomyopathy (DCM) were investigated by equilibrium right ventricular blood pool scintigraphy using ultrashort-lifetime 81mKr. Thirteen patients with severe left ventricular dysfunction due to old anterior myocardial infarction (OMI) and nine normal subjects were used as controls. The right ventricular end-diastolic pressure and volume index, mean pulmonary arterial pressure, and total pulmonary vascular resistance index were almost the same in the DCM and OMI patients. The right ventricular ejection fraction was 44.2 +/- 6.0% (mean +/- SD) in DCM patients and 47.1 +/- 7.9% in OMI patients, both significantly lower than those in the normal subjects (54.5 +/- 5.3%), but with no difference between the two case groups. The right ventricular peak filling rate was significantly reduced in both case groups as compared with the normal subjects (2.46 +/- 0.81 EDV/sec). The reduction was significantly greater (p < 0.05) in the DCM group (0.97 +/- 0.47 EDV/sec) than in the OMI group (1.61 +/- 0.46 EDV/sec). Cineangiography showed that the wall motion abnormality of the interventricular septum was remarkable in OMI patients, but was relatively mild in DCM patients. Lesions of the interventricular septum may be of major importance in right ventricular dysfunction in OMI, while extensive severe damage to the right ventricular free wall may be important in DCM. 81mKr blood pool scintigraphy is useful in the study of the right ventricular systolic and diastolic function. The diastolic parameters are more sensitive indicators for evaluation of right ventricular function in DCM than the systolic parameters.     

Right ventricular volume characteristics in ventricular septal defect

Right and left ventricular volume characteristics were determined from biplane cineangiocardiography in 37 patients with isolated ventricular septal defects. Patients were divided into three categories as determined by the degree of left-to-right shunt: small shunt-less than 35% of pulmonary blood flow (N=9); moderate shunt-35-49% (N=8), and large shunt-greater than 50% (N=20). Right ventricular (RV) end-diastolic volume was increased above normal in 15 of 20 studies performed in patients with large left-to-right shunts and averaged 159 +/- 10% of normal (P less than 0.001). In contrast, only one of the patients in the small shunt group and only half of the patients in the moderate shunt group showed increases in RV end-diastolic volume. The increase in RV volume was proportional to the corresponding increase in left ventricular end-diastolic volume, with the right ventricle ranging from 48 to 116% of LV end-diastolic volume (average 83%). Right ventricular ejection fraction was normal in all patient groups. Right ventricular outpur was increased commensurate with the increases in the RV end-diastolic volume. These data indicate that substantial augmentation in RV end-diastolic volume does occur in patients with isolated ventricular septal defects and large left-to-right shunts. These data can be explained by the significant diastolic and "isovolumic" shunting from left ventricle to right ventricle which occurs in these patients.     

Right ventricular ejection fraction is an independent predictor of survival in patients with moderate heart failure

OBJECTIVES: We sought to study the relationship between survival and right ventricular ejection fraction (RVEF) in a subgroup of patients with moderate congestive heart failure (CHF). BACKGROUND: It has been demonstrated that RVEF is an independent predictor of survival in patients with advanced CHF. METHODS: Cardiopulmonary exercise testing and radionuclide angiography (to determine right and left ventricular ejection fraction) were prospectively performed in 205 consecutive patients with moderate CHF (140 patients in New York Heart Association [NYHA] class II, 65 in class III). RESULTS: Left ventricular ejection fraction was 29.3%+/-10.1%, RVEF was 37.5%+/-14.6% and peak oxygen consumption (VO2) was 16.2+/-5.4 ml/min/kg (60.2%+/-19% of maximal predicted VO2). After a median follow-up period of 755 days, there were 44 cardiac-related deaths, 3 deaths from noncardiac causes and 15 transplantations of whom 2 were urgent; 1 patient was lost to follow-up. Multivariate analysis showed that three variables-NYHA classification, percent of maximal predicted VO2 and RVEF-were independent predictors of both survival and event-free cardiac survival. Left ventricular ejection fraction and peak VO2 normalized to body weight had no predictive value. The event-free survival rates from cardiovascular mortality and urgent transplantation at 1 year were 80%, 90% and 95% in patients with an RVEF <25%, with a RVEF > or =25% and <35% and with a RVEF > or =35%, respectively. At 2 years, survival rates were 59%, 77% and 93% in the same subgroups, respectively. CONCLUSIONS: In addition to the NYHA classification and to the percent of maximal predicted VO2, RVEF is an independent predictor of survival in patients with moderate CHF.     

MRI evaluation of right ventricular pressure overload in chronic obstructive pulmonary disease

In chronic obstructive pulmonary disease (COPD), the development of pulmonary hypertension is common. This study was performed to assess the signs of right ventricular (RV) pressure overload and RV failure in COPD. In 8 COPD patients without primary cardiac disease, RV wall thickness, mass, and end-diastolic volume were measured by cardiac-triggered cine MRI. MR phase-contrast velocity quantification was used to measure stroke volume and the patterns of flow into and out of the RV. Data of patients were tested versus those of a control group matched for age (n = 8). Results showed that the RV wall thickness was increased (.6 +/- 0.1 vs 0.4 +/- 0.1 cm, P < .001). RV mass was increased (67 +/- 11 vs 57 +/- 5 g, P < .005). RV stroke volume was decreased (57 +/- 13 vs 71 +/- 13 ml, P < .01), but RV ejection fraction was not different. In the main pulmonary artery flow, the quotient of acceleration time divided by ejection time was decreased (33 +/- 5% vs 38 +/- 4%, P < .05), which is indicative of pulmonary hypertension. In conclusion, this MRI protocol provides a tool to assess the effects of RV pressure overload in COPD before heart failure has become manifest.     

Tibiofibular syndesmosis: high-resolution MRI using a local gradient coil

The purpose of this study was to validate the accuracy of the assessment of ventricular function by first-pass radionuclide angiography (FPRNA) with 123I myocardial tracers and a multicrystal gamma camera. METHODS: Left ventricular ejection fraction (LVEF) and right ventricular ejection fraction were measured in 69 patients by FPRNA using 123I myocardial tracers (126 +/- 7 MBq) and 99mTc tracers (541 +/- 141 MBq) on a multicrystal gamma camera with a high-sensitivity collimator. For 44 patients, ejection fraction values measured by 123I-FPRNA were compared to those estimated by equilibrium radionuclide angiography (ERNA). Visual wall-motion analysis was also performed to judge clinical acceptability of 123I-FPRNA images for identification of wall-motion abnormality. RESULTS: Mean LVEFs (%) estimated by 123I-FPRNA and by 99mTc-FPRNA were 49.6 +/- 13.6 and 49.1 +/- 14.1, respectively (nonsignificant p value). An excellent correlation was found between LVEFs estimated by 123I-FPRNA and 99mTc-FPRNA (r = 0.96, s.e.e. = 1.9%). Values of LVEF measured by 123I-FPRNA also demonstrated excellent correlation with those measured by ERNA (r = 0.95, s.e.e. = 2.2%). A good correlation was also noted between right ventricular ejection fractions measured by 123I-FPRNA and 99mTc-FPRNA (r = 0.72, s.e.e. = 4.0%). The Spearman rank correlation coefficient between 123I-FPRNA and ERNA wall-motion scores was 0.87 (n = 135, p < 0.001). CONCLUSION: Resting ventricular function can be reliably measured with 123I-FPRNA in combination with a multicrystal gamma camera. This indicates that the assessment of ventricular function is feasible in conjunction with 123I myocardial imaging without an increase in cost or radiation dose to patients.     

Surgical treatment of ischemic heart disease complicated with severe left ventricular dysfunction: experience in 200 cases

BACKGROUND: The study was designed to evaluate short and long-term benefits of coronary artery bypass graft in patients with coronary artery disease and severely depressed left ventricular ejection fraction and to identify contemporary risk factors associated with significantly greater mortality in this high-risk subgroup. METHODS: From 1985 to 1995, 200 consecutive pts with EF < or = 0.30 underwent CABG. Among these patients, 60% were older than 70 years. NYHA functional class III/IV was present in 31% of pts. Preoperative mean cardiac index was 2.7 +/- 7 l/min/m2, mean pulmonary artery pressure was 29.9 +/- 7 mm Hg and contractility score (generated by appropriate software for left ventricular kinesis analysis) mean value was 50.1 +/- 11.6 points. Urgent operation was required in 32 pts (16%). The majority of pts were completely revascularized. RESULTS: Operative mortality was 9% (18 pts). Low output syndrome was the most common postoperative complication (13.5%) followed by ventricular arrhythmia (8%), mean length of postoperative hospitalization for survivors was 13 +/- 10 days. Of 23 possible operative risk factors evaluated, four were associated with significantly greater mortality: cardiac index < or = 2.1 l/min/m2, urgent operation, contractility score > or = 80 and associated surgical procedures. Survivors experienced significant improvement in CHF class (p < 0.001) and follow up EF (p < 0.001). Kaplan-Meier estimate of survival at 1 year, 5 years and 8 years was 85%, 65% and 54%. CONCLUSION: Through more careful assessment of preoperative risk factors, patients selection and perioperative management, actually coronary artery bypass graft may be offered to pts with low ejection fraction with reduced morbidity and mortality.     

ST-segment elevation in right precordial leads implies depressed right ventricular function after acute inferior myocardial infarction

BACKGROUND: The prognosis of acute inferior myocardial infarction is worse when it is complicated by right ventricular infarction. ST elevation in the right precordial leads is one of the reliable methods for detecting acute right ventricular infarction. The purpose of the study was to examine the relation between ST elevation in the right precordial electrocardiographic leads during acute inferior infarction and the severity of right ventricular systolic dysfunction. METHODS: This study analyzed the relation between ST elevation > or = 0.1 mV in V4R and the severity of right ventricular systolic dysfunction in 43 consecutive patients (men/women: 35/8; average age 62+/-9 years) with acute inferior myocardial infarction with a rapid-response Swan-Ganz catheter to measure the right ventricular ejection fraction (RVEF). RESULTS: RVEF was significantly lower in patients with ST elevation (n = 18) than in those without (n = 25) (33%+/-6% vs 40%+/-9%, p = 0.010). If the infarct-related lesion was located in the proximal right coronary artery, RVEF tended to be lower than if the lesion was located in the distal right coronary artery or the left circumflex coronary artery (33%+/-10% vs 37%+/-9% vs 42%+/-9%, p = 0.101). Logistic regression analysis demonstrated that ST elevation in V4R was the only independent predictor of depressed RVEF (odds ratio = 5.31, 95% confidence interval = 1.28 to 22.1, p = 0.022). CONCLUSION: ST elevation in lead V4R during acute inferior myocardial infarction predicts right ventricular systolic dysfunction.     

Pulmonary responses to 5-hydroxytryptamine and endothelin-1 in a rabbit model of left ventricular dysfunction

OBJECTIVE: To determine whether pulmonary hypertension developed in a coronary artery-ligated rabbit model of left ventricular dysfunction (LVD) and to examine the effects of i.v. 5-hydroxytryptamine (5-HT) and endothelin-1 (ET-1) on pulmonary arterial pressure (PAP). METHODS: Eight weeks after experimental coronary artery ligation or sham operation, ejection fractions were assessed by echocardiography. The rabbits were later anaesthetised and pulmonary arterial pressure was measured via a catheter inserted into the pulmonary artery via the right external jugular vein. 5-HT (1-400 micrograms/kg) and ET-1 (0.001-4 nmol/kg) were administered i.v. RESULTS: Ejection fraction was significantly decreased from 76.6 +/- 1.4% in sham-operated to 42.2 +/- 1.3% in coronary artery-ligated rabbits (n = 9 in each group; P < 0.001), consistent with LVD. Baseline mean pulmonary arterial pressure was significantly increased in the coronary artery-ligated group compared to the shams, (16.5 +/- 0.5 vs. 11.5 +/- 0.8 mmHg; P < 0.001). A significant degree of right ventricular hypertrophy was found in the coronary artery-ligated rabbits (0.70 +/- 0.04 g/kg final body weight (f.b.wt.), n = 8 cf. 0.48 +/- 0.02 g/kg f.b.wt. in sham-operated controls, n = 8; P < 0.001). There was a significant increase in the percentage of muscularised pulmonary vessels adjacent to alveolar ducts and alveoli < 60 microns i.d. in the LVD rabbits compared with their sham-operated controls (8.5 +/- 0.4 cf. 20 +/- 0.5%; P < 0.0005). 5-HT produced a greater response in the coronary artery-ligated rabbits (a maximum increase of 8.7 +/- 1.0 mmHg in mean pulmonary artery pressure vs. 4.6 +/- 1.5 mmHg for sham-operated controls; P < 0.05). ET-1 did not have any effect on pulmonary arterial pressure in either group. CONCLUSION: In the rabbit, LVD secondary to coronary artery ligation, causes right ventricular hypertrophy, pulmonary vascular remodelling, and an increased PAP consistent with the onset of pulmonary hypertension (PHT). The greater PAP response to i.v. 5-HT in the PHT group supports the hypothesis that this substance could be involved in the development of PHT. A role for ET-1 cannot be excluded, despite its lack of effect on PAP when intravenously administered in either group.