Right ventricular aneurysm associated with postinfarction ventricular septal defect

Isolated right ventricular aneurysms are rare. Postinfarction right ventricular aneurysm associated with a ventricular septal defect is a very unusual complication. We present such a case that was successfully treated surgically.     

Two cases of ventricular parasystole associated with ventricular tachycardia

In two patients, ventricular parasystole (VP) was associated with ventricular tachycardia (VT), and in one patient, catheter ablation was successful. In patient 1, with dilated cardiomyopathy, VP led to VT, which converted to ventricular fibrillation. In patient 2, VP led to symptomatic nonsustained polymorphic VT. The origin of parasystolic focus was determined by endocardial mapping, and a radiofrequency current was delivered to patient 2. Both VP and VT disappeared immediately, and no recurrence has been observed during a follow-up of 8 months. Catheter ablation to the parasystolic focus was effective and a relationship between VP and VT was strongly suggested.     

Overcoming right ventricular failure with left ventricular assist devices

BACKGROUND: Right ventricular failure can lead to circulatory collapse while on left ventricular assist device support. By shunting blood from the femoral vein to the left ventricular assist device, cardiac output can be increased, but arterial oxygen saturation will decrease. METHODS: To determine the effects on O2 delivery, a model was developed on the basis of O2 uptake in the lungs and whole body O2 consumption. An equation was derived that related cardiac output, pulmonary venous O2 saturation, O2 consumption, and the ratio of shunt-to-systemic blood flow to systemic O2 delivery. RESULTS: When total cardiac output increases, the shunt will increase systemic O2 delivery while decreasing arterial O2 saturation and leaving systemic venous O2 saturation unaltered. When total output does not increase, the shunt will decrease systemic O2 delivery, arterial O2 saturation, and systemic venous O2 saturation. CONCLUSIONS: The analysis suggests that measuring systemic venous oxygen saturation may be a useful way to monitor patient safety. A decrease in systemic venous O2 saturation when creating the shunt implies an inadequate increase in cardiac output.     

Repair of left ventricular diverticulum with ventricular bigeminy in an infant

Surgical repair of left ventricular diverticulum usually is not required in infancy even though it combines with other anomalies. In addition to prevention of rupture of the diverticulum and thrombus formation, treatment of combined ventricular tachycardia is thought to be an indication for resection of the diverticulum. We describe a successful repair performed by excising the isolated left ventricular diverticulum under cardiopulmonary bypass in a 9-day-old infant. The combined ventricular bigeminy has disappeared 9 months after the operation.     

Left ventricular regional systolic motion in patients with right ventricular pressure overload

The highly reactive and cytotoxic hydroxyl radical (OH) was found by electrochemical detection to be produced in reactions involving hydrogen peroxide (H2O2) and the nitric oxide (NO) donor diethylamine- NO complex. Using aromatic hydroxylation of salicylate as a specific indicator of OH, three salicylate hydroxylation products were identified; catechol, 2,3- and 2,5-dihydroxybenzoic acid. Four additional compounds were detected but not identified. The interactions of H2O2 and NO represent a biologically feasible reaction mechanism that can account for OH-induced damage in cellular environments where transition metal ions are unavailable for participation in the superoxide-mediated Fenton reaction. The ability of the NO/H2O2 complex to generate OH independently of iron or other transition metals provides a new focus for studies concerned with the origin of tissue-specific damage caused by oxygen-derived species.     

Churg-Strauss syndrome with right ventricular tumor

HISTORY AND CLINICAL FINDINGS: A 47-year-old woman was admitted because of diarrhoea (3-5 stools daily) for 9 days, weakness for 3 weeks and painful wrist swelling, arthralgia and hyperesthesia over the medial aspect of the right thigh for 6 weeks. For 6 years she had been treated for asthma. Two operation had been performed for chronic sinusitis. ADMISSION FINDINGS AND INVESTIGATIONS: There was marked eosinophilia (5889/microliter) and thrombocytopenia (96,000/microliter), markedly increased serological inflammatory parameters and a raised total IgE level (134 IU/ml). The chest radiogram showed pulmonary infiltrates and bone marrow biopsy indicated eosinophilia. Echocardiography revealed a mass, 3 x 8 cm, in the ventral wall of the right ventricle with extension into the outflow tract. DIAGNOSIS, TREATMENT AND COURSE: These findings met the criteria of the American College of Rheumatology for Churg-Strauss syndrome (CSS). On methylprednisolone (1 mg/kg daily) the eosinophil and platelet counts became normal within 5 days and erythrocyte sedimentation rate and the level of C-reactive protein fell. Under cardiopulmonary bypass the tumour was removed, the tricuspid valve replaced, and the right ventricle reconstructed. Histology of the mass revealed it to be an organized thrombus. CONCLUSION: The relationship between the thrombus formation and CSS is unclear. Hypercoagulability connected with the inflammatory process may have played a part in the pathogenesis.     

Left ventricular contractile performance, ventriculoarterial coupling, and left ventricular efficiency in hypertensive patients with left ventricular hypertrophy

Contractile performance of hypertrophied left ventricle may be depressed in arterial hypertension. Ventriculoarterial coupling is impaired when myocardial contractile performance is reduced and when afterload is increased. The left ventricular contractile performance and the ventriculoarterial coupling were evaluated in 30 hypertensive patients with moderate left ventricular hypertrophy and 20 control subjects. Left ventricular angiography coupled with the simultaneous recording of pressures with a micromanometer were used to determine end-systolic stress/volume index, the slope of end-systolic pressure-volume relationship, ie, end-systolic elastance, effective arterial elastance, external work, and pressure-volume area. In hypertensive patients, left ventricular contractile performance, as assessed by end-systolic elastance/ 100 g myocardial mass, was depressed (4.35 +/- 1.13 v 5.21 +/- 1.89 mm Hg/mL/100 g in control subjects P < .02), when end-systolic stress-to-volume ratio was comparable in the two groups (3.85 +/- 0.99 g/cm2/mL in hypertensive patients versus 3.51 +/- 0.77 g/cm2/mL in control subjects). Ventriculoarterial coupling, evaluated through effective arterial elastance/end-systolic elastance ratio, was slightly higher in hypertensive patients (0.53 +/- 0.08 v 0.48 +/- 0.09 mm Hg/mL in control subjects, P < .05), and work efficiency (external work/pressure-volume area) was similar in the two groups (0.78 +/- 0.04 mm Hg/mL in hypertensive patients versus 0.80 +/- 0.03 mm Hg/mL in control subjects). This study shows that despite a slight depression of left ventricular contractile performance, work efficiency is preserved and ventriculoarterial coupling is almost normal in hypertensive patients with left ventricular hypertrophy. Thus, it appears that left ventricular hypertrophy might be a useful means of preserving the match between left ventricle and arterial receptor with minimal energy cost.     

Left ventricular diastolic filling with an implantable ventricular assist device: beat to beat variability with overall improvement

OBJECTIVES: We studied the effects of left ventricular (LV) unloading by an implantable ventricular assist device on LV diastolic filling. BACKGROUND: Although many investigators have reported reliable systemic and peripheral circulatory support with implantable LV assist devices, little is known about their effect on cardiac performance. METHODS: Peak velocities of early diastolic filling, late diastolic filling, late to early filling ratio, deceleration time of early filling, diastolic filling period and atrial filling fraction were measured by intraoperative transesophageal Doppler echocardiography before and after insertion of an LV assist device in eight patients. A numerical model was developed to simulate this situation. RESULTS: Before device insertion, all patients showed either a restrictive or a monophasic transmitral flow pattern. After device insertion, transmitral flow showed rapid beat to beat variation in each patient, from abnormal relaxation to restrictive patterns. However, when the average values obtained from 10 consecutive beats were considered, overall filling was significantly normalized from baseline, with early filling velocity falling from 87 +/- 31 to 64 +/- 26 cm/s (p < 0.01) and late filling velocity rising from 8 +/- 11 to 32 +/- 23 cm/s (p < 0.05), resulting in an increase in the late to early filling ratio from 0.13 +/- 0.18 to 0.59 +/- 0.38 (p < 0.01) and a rise in the atrial filling fraction from 8 +/- 10% to 26 +/- 17% (p < 0.01). The deceleration time (from 112 +/- 40 to 160 +/- 44 ms, p < 0.05) and the filling period corrected by the RR interval (from 39 +/- 8% to 54 +/- 10%, p < 0.005) were also significantly prolonged. In the computer model, asynchronous LV assistance produced significant beat to beat variation in filling indexes, but overall a normalization of deceleration time as well as other variables. CONCLUSIONS: With LV assistance, transmitral flow showed rapidly varying patterns beat by beat in each patient, but overall diastolic filling tended to normalize with an increase of atrial contribution to the filling. Because of the variable nature of the transmitral flow pattern with the assist device, the timing of the device cycle must be considered when inferring diastolic function from transmitral flow pattern.     

Double ventricular parasystole associated with atrial fibrillation

The case of a 75-year-old man with acute myocardial infarction is presented. Two ventricular parasystolic foci, one in the right bundle branch, the other in the left bundle branch system were demonstrated with the aid of a His bundle recording, in the presence of atrial fibrillation.     

Treatment of ventricular dysphonia with botulinum toxin

Ventricular dysphonia, traditionally known as dysphonia plica ventricularis, is a voicing disorder in which the false vocal folds are used as a vibratory source in addition to or instead of the true vocal folds. Traditional treatment of ventricular dysphonia has been voice therapy, which may be slow to produce results if the false fold activity masks an underlying problem of the true folds, is long standing, or has produced hypertrophy of the supraglottic structures. We present seven cases of ventricular dysphonia treated with botulinum toxin injection into the false vocal folds followed by speech therapy. The addition of botulinum toxin to the treatment regimen speeds recovery of normal voicing and allows immediate evaluation of dynamic true vocal fold function by the treating professional.     

Freon inhalational abuse presenting with ventricular fibrillation

Inhalation of volatile halogenated hydrocarbons may produce life-threatening cardiac and neurological toxicity. A 15-year-old boy developed ventricular fibrillation immediately after intentional inhalation of a fluorinated hydrocarbon from an automobile air conditioner recharge unit. After the use of intravenous bretylium, a hemodynamically stable sinus tachycardia was restored. Aspiration pneumonitis and rhabdomyolysis complicated his hospital course before complete neurological recovery. The mechanism and treatment of cardiac arrhythmias after volatile fluorinated hydrocarbon inhalation are reviewed.     

Left ventricular geometry and severe left ventricular hypertrophy in children and adolescents with essential hypertension

BACKGROUND: Left ventricular (LV) hypertrophy has been established as an independent risk factor for cardiovascular disease in adults. Recent research has refined this relationship by determining a cutpoint of 51 g/m(2.7) for LV mass index indicative of increased risk and defining LV geometric patterns that are associated with increased risk. The purpose of this study was to evaluate severe LV hypertrophy and LV geometry in children and adolescents with essential hypertension. METHODS AND RESULTS: A cross-sectional study of young patients (n=130) with persistent blood pressure elevation above the 90th percentile was conducted. Nineteen patients (14%) had LV mass greater than the 99th percentile; 11 of these were also above the adult cutpoint of 51 g/m(2.7). Males, subjects with greater body mass index, and those who had lower heart rate at maximum exercise were at significantly (P<.05) higher risk of severe LV hypertrophy. In addition, 22 patients (17%) had concentric LV hypertrophy, a geometric pattern that is associated with increased risk of cardiovascular disease in adults. Seven patients had LV mass index above the cutpoint and concentric hypertrophy. No consistent significant determinants of LV geometry were identified in these children and adolescents with hypertension. CONCLUSIONS: Severe LV hypertrophy and abnormal LV geometry are relatively prevalent in young patients with essential hypertension. These findings suggest that these patients may be at risk for future cardiovascular disease and underscore the importance of recognition and treatment of blood pressure elevation in children and adolescents. Weight loss is an important component of therapy in young patients with essential hypertension who are overweight.     

Coronary reserve and right ventricular function in awake newborn lambs with persistent right ventricular hypertension

Right ventricular function curves as measured by right ventricular stroke work were normal in all control lambs, whereas three of five lambs with banded pulmonary arteries had relatively flat curves. Left ventricular function was similarly normal in the control group as compared to a near zero slope function curve in the banded group. Regional myocardial blood flow to the septum and right and left ventricles was similar in control and banded lambs. At rest right ventricular coronary vascular resistance was lower in the banded than in the control group and decreased in both groups during both isoproterenol and dextran stress states. In general, both groups had a similar ratio of right to left ventricular oxygen supply to demand ratio. These results show first that there is minimal, if any, biventricular functional reserve in lambs with persistent right ventricular hypertension, and second, that there is substantial coronary vascular reserve in both normal and banded groups.     

Aneurysm of the membranous ventricular septum with ventricular septal defect, mitral and tricuspid insufficiency

Bile acids are known to promote colon carcinogenesis. However, there is one study showing that ursodeoxycholic acid (UDCA) supplemented in the diet at the concentration of 0.4% prevented azoxymethane-induced rat colon tumorigenesis. The aim of our study was to explore the inhibitory effect of a much smaller dose of UDCA on colon carcinogenesis in rats. One hundred 7-week-old F344 rats were given 2 mg of N-methylnitrosourea 3 times a week for 3 weeks by intrarectal instillation, and were fed a 0% (control), 0.4% or 0.08% UDCA-supplemented diet for the next 27 weeks. All the rats were killed and examined for tumor development at week 30. The tumor incidence and number were significantly lower and smaller, respectively, in the UDCA-fed rats than in the control rats: 40% and 36% vs. 68%; 0.5 +/- 0.1 (mean +/- SEM) and 0.4 +/- 0.1 vs. 1.0 +/- 0.2. All the tumors were located in the distal half of the colon and were plaque-shaped or polypoid, being well-differentiated adenocarcinomas restricted to the mucosa or submucosa. Bile acids in the feces and the blood obtained at weeks 20 and 30, respectively, were analyzed by HPLC. A significant increase of UDCA was confirmed in both the feces and the blood of the UDCA-fed rats compared with the control rats. The results suggest that the continuous feeding of a small dose of UDCA may prevent colon carcinogenesis.     

Hemodynamic benefits of right ventricular outflow tract pacing: comparison with right ventricular apex pacing

To assess optimal hemodynamics in relation to stimulation site during right ventricular pacing, 17 consecutive patients who underwent cardiac catheterization were studied. In all patients, right ventricular apex and right ventricular outflow tract stimulation was performed at 85, 100, and 120 beats/min. Cardiac index at both pacing sites was compared using the left ventricular outflow tract continuous wave Doppler technique. Comparison of the two stimulation sites demonstrated that right ventricular outflow tract pacing resulted in a higher cardiac index at 85 beats/min (2.42 +/- 1.2 vs 2.04 +/- 1.0 L/min per m2, P < 0.002) at 100 beats/min (2.78 +/- 1.4 vs 2.35 +/- 1.1 L/min per m2, P < 0.001) and 120 beats/min (3.00 +/- 1.5 vs 2.61 +/- 0.9 L/min per m2, P < 0.001). From a total of 51 paired observations, 45 showed an increase in cardiac index during outflow tract pacing as compared to apex pacing. Right ventricular outflow tract pacing at 120 beats/min resulted in a lower cardiac index than right ventricular apex pacing in patients with significant coronary artery disease and/or impaired left ventricular function (ejection fraction < or = 50%), whereas right ventricular outflow tract pacing produced higher cardiac indices in the absence of these abnormalities. Right ventricular outflow tract pacing resulted in higher cardiac indices as compared to apex pacing in all other subgroups at all other pacing sites tested. It is concluded that stimulation of the right ventricular outflow tract offers a significant hemodynamic benefit during single chamber pacing as compared to conventional apex pacing, particularly in the absence of significant coronary artery disease and/or left ventricular dysfunction.     

Right ventricular diastolic disfunction and its relation to left ventricular performance in patients with hypertension

The potential effects of propofol emulsion (Diprivan) on the neuromuscular transmission and muscular contraction were studied using in vitro and in vivo nerve-muscle preparations of rats. The contractions of the isolated rat diaphragm elicited by either indirect or direct electrical stimulation were inhibited by propofol emulsion at threshold concentrations of 42 and 112 mumol l-1, respectively. Similarly, the gastrocnemius muscle contractions induced by either indirect or direct electrical stimulation in vivo were inhibited by propofol emulsion administration as a bolus injection of 2.5 mg kg-1 intravenously, followed by intravenous infusion of 150 micrograms kg-1 min-1 for 1 h into rats. The inhibitory effects of propofol in both preparations were greater with indirect rather than direct stimulation. Propofol emulsion was found to be capable of enhancing the paralysis of the indirectly stimulated rat diaphragm in vitro and gastrocnemius muscle in vivo induced by either pipecuronium or succinylcholine. The combination of propofol and pipecuronium led to a synergistic inhibition of the neuromuscular transmission, while the combination of propofol and succinylcholine led to additive inhibition. Pretreatment with propofol emulsion at these threshold concentrations markedly inhibited the stimulant effects of aminophylline and digoxin on the indirectly and directly induced diaphragmatic contractions. Also, the enhancement effects of aminophylline on the indirectly and directly and of digoxin on indirectly induced rat gastrocnemius muscle contractions were markedly inhibited by propofol emulsion administration to rats. Pretreatment with propofol emulsion at the threshold concentrations enhanced the inhibitory effects of verapamil on diaphragmatic contractions elicited either indirectly or directly and enhanced the inhibitory effect of adenosine on the contractions elicited indirectly. Similarly, the inhibitory effects of verapamil on the indirectly and directly and of adenosine on indirectly induced rat gastrocnemius muscle contractions were markedly potentiated by propofol emulsion administration to rats. In addition, doubling the concentration of calcium in the bathing fluid produced no change in the inhibitory effects of propofol emulsion on either indirectly or directly elicited diaphragmatic contractions, while doubling the concentration of external magnesium potentiated the propofol effects. Pretreatment with 4-aminopyridine suppressed the inhibitory effects of propofol emulsion on diaphragmatic contractions elicited either indirectly or directly. These results suggest that propofol acts presynaptically to inhibit the neuromuscular transmission and acts at the muscle membrane to inhibit the muscular contraction.     

Effect of relatively low dose amiodarone therapy on left ventricular function in patients with ventricular tachyarrhythmias

The effect of oral amiodarone (AMD) therapy on left ventricular (LV) function was evaluated retrospectively in Japanese patients with ventricular tachyarrhythmias and congestive heart failure. Seventeen patients were treated with oral AMD (maintenance dose 191+/-52mg/day) for more than 12 months. Fractional shortening (FS) on echocardiography revealed a trend towards an increase in the short-term (3 months) (p=0.06), but was not significant in the long-term follow-up period (more than 12 months) after AMD therapy. In 8 patients with 1 episode of myocardial infarction, FS revealed a trend towards an increase (p=0.09). In all of the 4 patients with dilated cardiomyopathy whose LV end-diastolic diameter was increased, FS was decreased in the long-term follow-up. Neither hospitalization frequency nor New York Heart Association classification were reduced by AMD therapy. In conclusion,oral AMD therapy did not cause LV function to recover significantly and could not improve the clinical course in patients with ventricular tachyarrhythmias. However, if the underlying disease is not progressive, AMD therapy may improve LV function.