Reversal of left ventricular hypertrophy in essential hypertension. A meta-analysis of randomized double-blind studies

OBJECTIVE: To determine the ability of various antihypertensive agents to reduce left ventricular hypertrophy, a strong, blood pressure-independent cardiovascular risk factor, in persons with essential hypertension. DATA SOURCES: MEDLINE, DIMDI, RINGDOC, ADES, EMBASE, and review articles through July 1995 (English-language and full articles only). STUDY SELECTION: Meta-analysis of all published articles including only double-blind, randomized, controlled clinical studies with parallel-group design. DATA EXTRACTION: Intensive literature search and data extraction according to a prefixed scheme performed independently by 2 investigators. Reduction of left ventricular mass index after antihypertensive therapy with placebos, diuretics, beta-blockers, calcium channel blockers, or angiotensin-converting enzyme (ACE) inhibitors was the principal parameter. DATA SYNTHESIS: Of 471 identified references describing the effects of antihypertensive drugs on left ventricular hypertrophy, only 39 clinical trials fulfilled the inclusion criteria of our study. We found that the decrease in left ventricular mass index was more marked the greater was the decline in blood pressure (systolic r=0.46, P<.001; diastolic r=0.21, P=.08) and the longer was the duration of therapy (r=0.38, P<.01). After adjustment for different durations of treatment (mean duration of treatment, 25 weeks), left ventricular mass decreased 13% with ACE inhibitors, 9% with calcium channel blockers, 6% with beta-blockers, and 7% with diuretics. There was a significant difference between drug classes (P<.01): ACE inhibitors reduced left ventricular mass more than beta-blockers (significant, P<.05) and diuretics (tendency, P=.08). Similar differences between drug classes were found with regard to effect on left ventricular wall thickness (P<.05). CONCLUSIONS: The database of articles published through July 1995 is small and incomplete, and most of the articles are of poor scientific quality. In this first meta-analysis including only double-blind, randomized, controlled clinical studies, decline in blood pressure, duration of drug treatment, and drug class determined the reductions in left ventricular mass index. The ACE inhibitors seemed to be more potent than beta-blockers and diuretics in the reduction of left ventricular mass index; calcium channel blockers were somewhat in the intermediate range. The ACE inhibitors and, to a lesser extent, calcium channel blockers emerged as first-line candidates to reduce the risk associated with left ventricular hypertrophy.     

Normal left ventricular ejection fraction in older persons with congestive heart failure

STUDY OBJECTIVES: To investigate in older patients with congestive heart failure (CHF) associated with prior myocardial infarction or hypertension the relationship between normal left ventricular (LV) ejection fraction and age, gender, hypertension, prior myocardial infarction, and atrial fibrillation. DESIGN: A prospective study was performed in 572 older patients (age >60 years) with CHF associated with prior myocardial infarction or hypertension and technically adequate two-dimensional echocardiograms for measuring LV ejection fraction. SETTING: A long-term health-care facility. PATIENTS: One hundred seventy-seven men and 395 women, mean age 82+/-8 years, with CHF associated with prior myocardial infarction or hypertension. MEASUREMENTS AND RESULTS: Normal LV ejection fraction (> or = 50%) occurred in 66 of 177 men (37%) and in 221 of 395 women (56%) (p<0.0001). Multiple logistic regression analysis showed that independent risk factors for normal LV ejection fraction in patients with CHF were no prior myocardial infarction (p=0.0001; odds ratio=3.048), female gender (p=0.0004; odds ratio=1.978), and age (p=0.016; odds ratio=1.029). CONCLUSIONS: Normal LV ejection fraction occurred in 50% of 572 older patients with CHF associated with prior myocardial infarction or hypertension. Independent risk factors for normal LV ejection fraction in patients with CHF were no prior myocardial infarction, female gender, and age.     

Effects of long-term monotherapy with enalapril, metoprolol, and digoxin on the progression of left ventricular dysfunction and dilation in dogs with reduced ejection fraction

BACKGROUND: Recent clinical trials have suggested that therapy with angiotensin-converting enzyme inhibitors in asymptomatic patients with reduced left ventricular (LV) function can significantly reduce the incidence of congestive heart failure compared with patients receiving placebo. In the present study, we examined the effects of long-term monotherapy with enalapril, metoprolol, and digoxin on the progression of LV systolic dysfunction and LV chamber enlargement in dogs with reduced LV ejection fraction (EF). METHODS AND RESULTS: LV dysfunction was produced in 28 dogs by multiple sequential intracoronary microembolizations. Embolizations were discontinued when LVEF was 30% to 40%. Three weeks after the last embolization, dogs were randomized to 3 months of oral therapy with enalapril (10 mg twice daily, n = 7), metoprolol (25 mg twice daily, n = 7), digoxin (0.25 mg once daily, n = 7), or no treatment (control, n = 7). As expected, in untreated dogs, LVEF decreased (36 +/- 1% versus 26 +/- 1%, P < .001) and LV end-systolic volume (ESV) and end-diastolic volume (EDV) increased during the 3-month follow-up period (39 +/- 4 versus 57 +/- 6 mL, P < .001, and 61 +/- 6 versus 78 +/- 8 mL, P < .002, respectively). In dogs treated with enalapril or metoprolol, LVEF remained unchanged or increased after therapy compared with before therapy (35 +/- 1% versus 38 +/- 3% and 35 +/- 1% versus 40 +/- 3%, respectively, P < .05), whereas ESV and EDV remained essentially unchanged. In dogs treated with digoxin, EF remained unchanged but ESV and EDV increased significantly. CONCLUSIONS: In dogs with reduced LVEF, long-term therapy with enalapril or metoprolol prevents the progression of LV systolic dysfunction and LV chamber dilation. Therapy with digoxin maintains LV systolic function but does not prevent progressive LV enlargement.     

Calcium channel blockers, cancer incidence, and cancer mortality in a cohort of U.S. women: the nurses' health study

BACKGROUND: Some studies have suggested that the use of calcium channel blockers may increase the risk of cancer. A possible association of the use of calcium channel blockers with cancer incidence and cancer mortality was addressed using data from the Nurses' Health Study. METHODS: In this study, a total of 18,635 female nurses reported regularly taking at least 1 of 4 cardiovascular medications in 1988: diuretics, beta-blockers, calcium channel blockers, and/or angiotensin-converting enzyme (ACE) inhibitors. Cancer incidence and cancer deaths were ascertained until 1994. RESULTS: During 6 years of follow-up, 852 women were newly diagnosed with cancer and 335 women died of cancer. Women who reported the use of calcium channel blockers had no increased risk of newly diagnosed cancer compared with those taking other cardiovascular drugs (relative risk=1.02; 95% CI 0.83-1.26). The relative risk of dying from cancer associated with the self-reported use of calcium channel blockers was 1.25 (95% CI 0.91-1.72). Relative risks were adjusted for the following self-reported factors: age; weight; height; cholesterol level; systolic and diastolic blood pressure; smoking; alcohol intake; physical activity; menopausal status; postmenopausal hormone use; aspirin use; and history of diabetes, cancer, stroke, myocardial infarction, coronary artery bypass graft or percutaneous transluminal coronary angioplasty, angina, and hypertension. Regarding site specific cancer incidence and mortality, only lung cancer incidence was somewhat increased (RR=1.61; 95% CI 0.88-2.96). CONCLUSIONS: These data suggest no important increase in overall cancer incidence or cancer mortality related to the self-reported use of calcium channel blockers.     

Use of digoxin, diuretics, beta blockers, angiotensin-converting enzyme inhibitors, and calcium channel blockers in older patients in an academic hospital-based geriatrics practice

OBJECTIVE: To investigate the prevalence of and indications for digoxin use and the prevalence of beta blocker and calcium channel blocker use in older patients with previous myocardial infarction or coronary artery disease (CAD), and the prevalence of use of diuretics, beta blockers, angiotensin-converting enzyme (ACE) inhibitors, and calcium channel blockers in older patients with hypertension in an academic hospital-based geriatrics practice. DESIGN: A retrospective analysis of charts from 528 unselected older patients, seen from June 1995 through July 1996 at an academic hospital-based geriatrics practice, was performed to investigate the prevalence of digoxin use and indications for digoxin use, the prevalence of beta blocker and calcium channel blocker use in older patients with previous myocardial infarction or coronary artery disease (CAD), and the prevalence of use of diuretics, beta blockers, angiotensin-converting enzyme (ACE) inhibitors, and calcium channel blockers in older patients with hypertension. SETTING: An academic hospital-based, primary care geriatrics practice staffed by fellows in a geriatrics training program and full-time faculty geriatricians. PATIENTS: A total of 416 women and 112 men, mean age 81 +/- 8 years (range 58 to 101), were included in the study. MEASUREMENTS AND MAIN RESULTS: Ninety-two of the 528 patients (17%) were taking digoxin. Recorded indications for digoxin were atrial fibrillation with or without congestive heart failure (CHF) in 39% of patients, CHF with sinus rhythm and abnormal left ventricular ejection fraction (LVEF) in 18% of patients, a clinical assessment of CHF with sinus rhythm and no recorded measurement of LVEF in 20% of patients, paroxysmal atrial fibrillation in 14% of patients, and coronary artery disease (CAD) in 9% of patients. Of 121 patients with previous myocardial infarction, 23 (19%) were prescribed beta blockers, and 54 (45%) were taking calcium channel blockers. Of 173 patients with CAD, 41 (24%) were treated with beta blockers, and 79 (46%) were taking calcium channel blockers. LVEF was not recorded in the charts of 90 of 121 patients (74%) with prior myocardial infarction and of 125 of 173 patients (72%) with CAD. Of 480 older patients with hypertension, 154 (37%) were treated with diuretics, 55 (13%) were treated with beta blockers, 160 (38%) were treated with ACE inhibitors, and 197 (47%) were treated with calcium channel blockers. CONCLUSIONS: In 528 older patients seen in an academic hospital-based geriatrics practice, the prevalence of digoxin use was 19%. Appropriate indications for digoxin were documented clearly in the charts of 53 of 92 patients (57%). Calcium channel blockers were used more often than beta blockers in patients with previous myocardial infarction or CAD. Calcium channel blockers were the most frequently used antihypertensive drugs.     

Symmetric and asymmetric left ventricular hypertrophy in patients with end-stage renal failure on long-term hemodialysis

BACKGROUND: Patients with end-stage renal disease on regular hemodialysis have an increased prevalence of left ventricular (LV) hypertrophy that is associated with morbidity and mortality. Asymmetric septal hypertrophy and impairment of LV outflow can occur in these patients and may contribute to adverse outcomes. More insight into the prevalence, extent, geometry, and promoting factors of LV hypertrophy is important. METHODS: An unselected group of 62 patients (31 women), aged 55 +/- 14 years, on maintenance hemodialysis was investigated by Doppler echocardiography. Eight patients with valvular heart disease were excluded from further analysis. We assessed prevalence of LV hypertrophy and asymmetric septal hypertrophy, as well as parameters of LV geometry and LV filling and outflow dynamics. RESULTS: Prevalence of LV hypertrophy was 65%. Patients were analyzed according to LV mass and geometry. Mean LV mass index was normal (105 +/- 17 g/m2) in Group 1 without LV hypertrophy (n = 19); it was markedly elevated in Group 2 (symmetric hypertrophy, n = 22) and Group 3 (asymmetric hypertrophy with systolic anterior movement of mitral valve, n = 7), and highest (191 +/- 54 g/m2) in Group 4 (asymmetric hypertrophy without systolic anterior movement of mitral valve, n = 6, p < 0.001). Age, body mass index, and duration of hypertension were associated with LV hypertrophy and asymmetric septal hypertrophy (p = 0.01). Group 3 with systolic anterior motion of mitral valve had the smallest end-diastolic LV diameters (p = 0.02); increased heart rates, and increased ejection velocities in the LV outflow tract (p = 0.03, and p = 0.005, respectively, vs. Groups 1, 2, and 4) which pointed to an impairment of LV outflow. CONCLUSIONS: Symmetric LV hypertrophy and asymmetric septal hypertrophy are frequent in patients on maintenance hemodialysis. Predictors for LV hypertrophy were age and body mass index, and, particularly for asymmetric septal hypertrophy, age and hypertension duration. Volume withdrawal during hemodialysis may lead to symptomatic hypotension due to dynamic obstruction in some patients with severe asymmetric septal hypertrophy.     

Overexpression, purification, and characterization of the cloned metallo-beta-lactamase L1 from Stenotrophomonas maltophilia

OBJECTIVES: The purpose of this study was to assess whether the presence or absence of myocardial viability during dobutamine echocardiography (DE) predicts survival in patients with coronary artery disease (CAD) and severe left ventricular (LV) dysfunction. BACKGROUND: In patients with CAD, the presence of myocardial viability during DE identifies viable myocardium and predicts recovery of LV systolic function after revascularization. However, there is little data on the relation between myocardial viability and clinical outcome in patients with CAD and severe LV dysfunction. METHODS: We studied 318 patients with CAD and a LV ejection fraction (EF) < or =35% who underwent DE and were followed for 18+/-10 months. Patients were classified into four groups. Group I (n=85) consisted of patients who had evidence of myocardial viability and subsequently underwent revascularization. Group II (n=119) consisted of patients with myocardial viability who did not undergo revascularization. Group III (n=30) consisted of patients who did not have myocardial viability and underwent revascularization. Finally, group IV (n=84) patients lacked myocardial viability and did not undergo revascularization. RESULTS: The four groups had similar baseline characteristics and rest LVEF. During follow-up there were 51 deaths (16%). The mortality rate was 6% in group I, 20% in group II, 17% in group III and 20% in group TV (p=0.01, group I vs. other groups). CONCLUSIONS: In patients with CAD and severe LV dysfunction who demonstrated myocardial viability during DE, revascularization improved survival compared with medical therapy.     

Temporal patterns of antihypertensive medication use among older adults, 1989 through 1992. An effect of the major clinical trials on clinical practice?

OBJECTIVE: To describe the changing patterns of antihypertensive medication use in the years immediately before and after the publication of the results of three major clinical trials of the treatment of hypertension in older adults. DESIGN: In this cohort study, adults 65 years or older were examined annually on four occasions between June 1989 and May 1992, and the use of antihypertensive medications was assessed by inventory at each visit. The four visits defined the boundaries of three study periods. For each study period, participants receiving antihypertensive therapy were either continuous users (n = 1667, 1643, and 1605, respectively) or starters (n = 157, 142, 120) of hypertensive therapy. The large clinical trials that convincingly proved the efficacy and safety of low-dose diuretic therapy in older adults were published during the latter parts of period 2 and the early parts of period 3. RESULTS: Among starters, the proportion initiating therapy on diuretics increased from 35.9% in period 2 to 47.5% in period 3, significantly so among women (P = .04). The proportions initiating other drugs displayed no significant trends. Among continuous users, the use of diuretics, beta-blockers, and vasodilators generally decreased over the 3-year period, while the use of calcium channel blockers and angiotensin-converting enzyme inhibitors increased significantly in each of the three periods (P < .05). The decline of 2.7% in the prevalence of diuretic use in period 1 abated during period 2 (1.8% decline), and it slowed significantly (P = .03) to almost a complete halt during period 3 (0.2% decline). The rate of increase in the use of calcium channel blockers slowed significantly (P = .01) between period 1 (+6.7%) and period 3 (+2.8%). CONCLUSIONS: Although other factors such as cost may have been important, the temporal trends in antihypertensive drug therapy coincided in time with and may have reflected in part the influence of the major clinical trials on the patterns of clinical practice.     

Intraoperative extra strong electrical stimulation in the treatment of peripheral nerve injury

OBJECTIVE: To explore the Yinji Capsule (YJC) in improving the left ventricular systolic function of angina pectoris patients with Blood Stasis Syndrome. METHODS: The systolic function of left ventricle (LV) in cardiac cycle of 28 angina pectoris patients with Blood Stasis Syndrome was examined with three-dimensional echocardiograph (3-DE) before and after treatment with YJC. RESULTS: The total symptomatic effective rate was 85.7%. The changes of LV systolic function were those: left ventricle ejection fraction (LVEF) increased from 45.0 +/- 4.9% to 48.2 +/- 3.5% (P < 0.05); EF on early stage and late stage increased from 22.6 +/- 2.1%, 8.3 +/- 1.2% to 28.1 +/- 3.0% and 10.3 +/- 0.9% respectively (P < 0.01, P < 0.05), myocardial region with segment systole (SS) < 5% decreased significantly (P < 0.01). CONCLUSION: YJC could improve LV systolic function on early stage and late stage in cardiac cycles, and mainly improve the systolic function of the region with low SS of LV.     

Safety and utility of atropine addition during dobutamine stress echocardiography for the assessment of viable myocardium in patients with severe left ventricular dysfunction

OBJECTIVE: To assess the feasibility safety and side effects of the addition of atropine to dobutamine stress echocardiography for the detection of viable myocardium in patients with left ventricular dysfunction (ejection fraction < or = 35%) prior to coronary revascularization. BACKGROUND: The assessment of viable and/or ischaemic myocardium has high prognostic value as regards improvement of function and survival after coronary revascularization. The addition of atropine to dobutamine during echocardiographic testing for the presence of viable myocardium is not common practice. Consequently, no data exist on the safety and additional diagnostic value of this practice. METHODS: Two hundred patients with left ventricular ejection fraction < or = 35% were studied. RESULTS: Test end-points were: target heart rate in 164 (82%) of the patients, severe angina in 18 (9%), maximum dobutamine-atropine dose in six (3%), severe ST segment changes in five (2%), cardiac arrhythmias in four (2%), and hypotension in three (1%). Viability could be assessed echocardiogaphically in 105/200 (53%) from a biphasic response (improvement of wall motion with low dose dobutamine and worsening with high dose), in 93 from ischaemia and in 12 from sustained or late improvements. In 36/105 (34%) patients, ischaemic myocardium could only be assessed after the addition of atropine. Cardiac arrhythmias occurred in 11/200 (6%) and hypotension (decrease of systolic blood pressure >30 mmHg) in 21/200 (11%). Neither the use of atropine nor the induction of ischaemia were associated with an increased incidence of cardiac arrhythmias or hypotension. CONCLUSIONS: In a large group of patients with severe left ventricular dysfunction, dobutamine stress echocardiography is feasible and safe in 186/200 (93%); the addition of atropine was necessary in 34% to assess myocardial viability. Hypotension and cardiac arrhythmias were the most frequent side effects, but were not related to the induction of ischaemia or addition of atropine.     

Determinants of the pulmonary artery pressure rise in left ventricular dysfunction

Pulmonary artery hypertension in patients with left ventricular dysfunction is related to poor outcome but the role of cardiac functional abnormalities in the genesis of pulmonary hypertension remains unknown. The aim of this prospective study was to identify the determinants of pulmonary hypertension in 102 consecutive patients with primary left ventricular dysfunction (ejection fraction < 50%). Systolic pulmonary artery pressure was measured by continuous wave Doppler. Left ventricular systolic and diastolic function, severity of functional mitral regurgitation, cardiac output, and left atrial volume were assessed using Doppler echocardiography. In patients with left ventricular dysfunction, systolic pulmonary artery pressure was increased (51 +/- 14 mmHg, range 23 to 87 mmHg). Mitral deceleration time (r = -0.61; p = 0.0001) and mitral effective regurgitant orifice (r = 0.50; p = 0.0001) were the strongest parameters related to systolic pulmonary artery pressure. Multivariate analysis identified these two variables as the strongest predictors of systolic pulmonary artery pressure in association with the mitral E/A ratio (p = 0.006) and age (p = 0.005). In conclusion, pulmonary hypertension is common and variable in patients with left ventricular dysfunction. It is closely related to diastolic dysfunction and severity of functional mitral regurgitation but not independently to the degree of left ventricular systolic dysfunction. These findings underline the importance of assessing diastolic function and quantifying mitral regurgitation in patients with left ventricular dysfunction.     

Stephen L. Gans Visiting Guest Lecture: central venous catheters for parenteral nutrition: a double-edged sword

The objective of this study was to critically evaluate the usefulness of atrial natriuretic factor (ANF), the N-terminal fragment of the ANF pro-hormone (pro-ANF) and B-type (brain) natriuretic peptide (BNP) determination as screening tests for identifying patients with mild left ventricular (LV) impairment. The sample consisted of a consecutive series of 254 patients undergoing diagnostic left-sided cardiac catheterization. Logistic regression analysis showed that plasma BNP was the best predictor of increased LV end-diastolic pressure, decreased LV ejection fraction and LV dysfunction (LV ejection fraction < or = 45% and LV end-diastolic pressure > or = 15 mm Hg). For the detection of LV dysfunction the areas under the receiver-operating characteristic function, an index of overall diagnostic accuracy, were 0.789 for BNP, 0.665 for ANF and 0.610 for pro-ANF. In conclusion, plasma BNP appears to be a better indicator of LV function than plasma ANF or pro-ANF. However, the overall diagnostic value of circulating ANF, pro-ANF, and BNP as indicators of mild LV dysfunction is relatively modest.     

Captopril and spironolactone therapy for refractory congestive heart failure

Short- and long-term clinical effects of the angiotensin-converting enzyme (ACE) inhibitor captopril in severe congestive heart failure (CHF) were evaluated during a 3-year open study of 124 inpatients with New York Heart Association (NYHA) functional class III or IV CHF refractory to treatment with cardiac glycosides and high doses of loop diuretics. Captopril was added to each patient's regimen, which comprised combinations of furosemide (124 patients), digitalis (117 patients), and spironolactone (90 patients). By the end of the first month of captopril administration, improvement in NYHA functional class was seen in 89 patients (72%). During the first year of captopril treatment, the number of hospital admissions and hospital days declined significantly (p < 0.001) and functional class improved significantly (p < 0.001). Although most patients tolerated captopril well, 44% experienced hypotension, which in 10% of patients necessitated termination of captopril therapy. Although mean serum potassium levels tended to increase, serious hyperkalemia did not occur. After 1 year, a subset of 30 patients who had not initially received spironolactone deteriorated clinically and manifested increasing urinary aldosterone levels. Hypotension precluded increasing the captopril dose, but introduction of spironolactone improved clinical status in this cohort. The results suggest that rational therapy for severe CHF includes addition of the aldosterone antagonist spironolactone to low doses of captopril (or another ACE inhibitor) and high doses of loop diuretics, provided renal function is adequate.     

Early versus delayed angiotensin-converting enzyme inhibition therapy in acute myocardial infarction. The healing and early afterload reducing therapy trial

BACKGROUND: Although ACE inhibitor therapy has been shown to reduce mortality in patients with acute myocardial infarction (MI), the optimal dose and the timing of its initiation have not been determined. METHODS AND RESULTS: In a double-blind trial of 352 patients with anterior MI, we compared the safety and effectiveness of early (day 1) versus delayed (day 14) initiation of the ACE inhibitor ramipril (10 mg) on echocardiographic measures of left ventricular (LV) area and ejection fraction (EF). An early, low-dose ramipril (0.625 mg) arm was also evaluated. Clinical events did not differ. During the first 14 days, the risk of manifesting a systolic arterial pressure of < or = 90 mm Hg was increased in both ramipril groups. LVEF increased in all groups during this period, but the early, full-dose ramipril group had the greatest improvement in EF (increase: full, 4.9 +/- 10.0; low, 3.9 +/- 8.2%; delayed, 2.4 +/- 8.8%; P for trend < .05) and was the only group that did not demonstrate a significant increase in LV diastolic area. CONCLUSIONS: The results of the present study demonstrated that in patients with anterior MI, the early use of ramipril (titrated to 10 mg) attenuated LV remodeling and was associated with a prompter recovery of LVEF. The use of low-dose regimen did not prevent hypotension and had only intermediate benefits on LV size and function. The more favorable effects on LV topography of the early use of full-dose ramipril support the results of the major clinical trials, which have demonstrated an early survival benefit of ACE inhibition.     

Symptomatic and asymptomatic left-ventricular systolic dysfunction in an urban population

BACKGROUND: In most previous epidemiological studies on the prevalence of chronic heart failure (CHF) the disorder has been defined on clinical criteria. In a cross-sectional survey of 2000 men and women aged 25-74, randomly sampled from one geographical area, we assessed left-ventricular systolic function by echocardiography. METHODS: 1640 (83%) of those invited took part. They completed a questionnaire on current medication, history, and symptoms of breathlessness. Blood pressure was measured and electrocardiography (ECG) and echocardiography were done. Left-ventricular ejection fraction was measurable in 1467 (89.5%) participants by the biplane Simpson's rate method. FINDINGS: The mean left-ventricular ejection fraction was 47.3%. The prevalence of definite left-ventricular systolic dysfunction (defined as a left-ventricular ejection fraction < or = 30%) was 2.9% overall (43 participants); it increased with age and was higher in men than in women (4.0 vs 2.0%). The left-ventricular systolic dysfunction was symptomatic in 1.5% of participants and asymptomatic in 1.4%, 83% of participants with left-ventricular systolic dysfunction had evidence of ischaemic heart disease (IHD) from history or ECG criteria compared with 21% of those without this abnormality (p < 0.001). Hypertension was also more common in those with left-ventricular systolic dysfunction (72 vs 38%, p < 0.001), but there was no difference between those with and without left-ventricular systolic dysfunction in the rate of hypertension without IHD. INTERPRETATION: Left-ventricular systolic dysfunction was at least twice as common as symptomatic heart failure defined by clinical criteria. The main risk factors are IHD and hypertension in the presence of IHD; screening of such high-risk groups for left-ventricular systolic dysfunction should be considered.     

Comparative toxicity of diuron on survival and growth of Pacific treefrog, bullfrog, red-legged frog, and African clawed frog embryos and tadpoles

The goal of treating hypertension is to maximize therapeutic efficacy without untoward side effects. The accepted approach is to start treatment with a low dose of a single drug and then titrate it upward as needed to achieve a better therapeutic effect. However, higher doses of administered individual drugs increase the frequency and severity of side effects. A rational combination of individual drugs administered in low doses is preferable because it is associated with a high degree of efficacy, low incidence or severity of side effects, and high patient compliance. The most commonly used drug combinations are as follows: (1) diuretics with potassium-sparing agents; (2) beta-adrenergic blockers with diuretics; (3) angiotensin-converting enzyme inhibitors with diuretics; (4) angiotensin II receptor blockers with diuretics; and (5) angiotensin-converting enzyme inhibitors with calcium-channel blockers.     

Isolation-stress-induced facilitation of passive avoidance memory in the day-old chick

Left ventricular (LV) midwall shortening (MWS) is subnormal in relation to LV circumferential end-systolic stress (ESS) (ESS-corrected MWS) in many hypertensive patients with normal LV chamber function and predicts subsequent morbidity and mortality. However, little is known of the relations of LV midwall function to demographic and metabolic variables or to arterial geometry. Asymptomatic, unmedicated normotensive (n=366) or hypertensive (n=282) adults were assessed with echocardiography and carotid ultrasound. In normal adults, lower LV MWS and ESS-corrected MWS, an index of LV contractility, were related independently to high total peripheral resistance, high heart rate, and male gender (all P<.00001), lower serum HDL cholesterol (P=.001) and diastolic pressure (P=.003), and for ESS-corrected MWS only, arterial relative wall thickness (RWT, P=.03). Among hypertensive patients, lower values for both midwall function indices were associated independently with higher peripheral resistance (P<.00001), heart rate (P<.00005), body mass index (P<.01), and arterial RWT (P=.04), as well as male gender (P<.0002). In the entire population, lower LV MWS was independently related to higher peripheral resistance, heart rate (both P<.00001), body mass index (P=.0006) and arterial RWT (P=.009); male gender (P<.00001); and lower age (P=.004), diastolic pressure (P=.042), and systolic carotid artery expansion (P=.032). Lower ESS-corrected MWS in the entire population was independently associated with higher peripheral resistance and heart rate (both P<.00001), body mass index (P=.0006), arterial RWT (P=.004); male gender; and lower diastolic pressure (both P<.00001), age (P<.00005), arterial expansion in systole (P=.006), and serum HDL cholesterol levels (P=.04). Among a subset (n=60), ESS-corrected MWS was positively related to apolipoprotein A1 (P=.004) and negatively to hemoglobin A1c (P<.01). Thus, higher LV midwall function is associated with female gender and more favorable profiles of hemodynamics, metabolic pattern, and arterial structure and function.     

Comparison of myocardial contrast echocardiography and low-dose dobutamine stress echocardiography in predicting recovery of left ventricular function after coronary revascularization in chronic ischemic heart disease

BACKGROUND: Dobutamine stress echocardiography (DSE) and myocardial contrast echocardiography (MCE) can predict recovery of left ventricular function after myocardial infarction. DSE also has been shown to predict left ventricular functional recovery after revascularization in chronic ischemic heart disease, whereas MCE has not been evaluated in such patients. This study was performed to compare DSE and MCE in the prediction of left ventricular functional recovery after revascularization in patients with chronic ischemic heart disease. METHODS AND RESULTS: MCE and DSE were performed in 35 patients with chronic coronary artery disease and significant wall motion abnormalities (mean ejection fraction, 0.36 +/- 0.09). Regional wall motion was scored by use of a 16-segment model wherein 1 = normal or hyperkinetic, 2 = hypokinetic, 3 = akinetic, and 4 = dyskinetic. Each segment was evaluated for contractile reserve by DSE and perfusion by MCE. Revascularization (coronary artery bypass graft [n = 13] and percutaneous transluminal coronary angioplasty [n = 10]) was successful in 23 patients. Follow-up echocardiograms were done to assess wall motion 30 to 60 days later. In 238 segments with resting wall motion abnormalities, perfusion was more likely to present than contractile reserve (97% versus 91%, P < .02). Revascularization resulted in functional recovery in 77 of 95 hypokinetic segments (81%) but only 18 of 57 akinetic segments (32%, P < .0001). DSE and MCE were not significantly different in predicting functional recovery of hypokinetic segments. In akinetic segments, DSE and MCE had similar sensitivities (89% versus 94%, respectively) and negative predictive values (93% and 97%, respectively) in predicting functional recovery. However, DSE had a higher specificity (92% versus 67%, P < .02) and positive predictive value (85% versus 55%, P < .02) than MCE in predicting functional recovery. CONCLUSIONS: Both contractile reserve by DSE and perfusion by MCE are predictive of functional recovery in hypokinetic segments after coronary revascularization in patients with chronic coronary revascularization in patients with chronic coronary artery disease. In akinetic segments, myocardial perfusion by MCE may exist in segments that do not recover contractile function after revascularization. Thus, contractile reserve during low-dose dobutamine infusion is a better predictor of functional recovery after revascularization in akinetic segments than perfusion.