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Biomedical subjects

M A Alpert

Publications and source records attributed to M A Alpert.

At least 91 records · Page 5Linked to original sources
PubMed1989

Can patients with chest pain and normal coronary arteries be discriminated from those with coronary artery disease prior to coronary angiography?

To determine whether the precatheterization clinical data in patients with chest pain could be used to discriminate patients with normal coronary arteries (NCA) from those with coronary artery disease, the authors compared 125 consecutive patients with less than 30% stenosis of all major coronary arteries and 125 patients with greater than 60% stenosis of one or more major coronary arteries. Clinical characteristics that occurred more frequently in patients with NCA were: nonexertional pain, pain to the left of the sternum, sharp pain, associated palpitations, absence of typical relief with sublingual nitroglycerin, pain commencing less than one week or more than ten years prior to coronary angiography, a normal electrocardiogram, and negative results from a treadmill stress test or from thallium scintigraphy. However, none of these clinical features, either singly or in combination, could be used to identify the patients with NCA with certainty.

Adult↗
PubMed1988

Sensitivity and specificity of electrocardiographic criteria for left and right ventricular hypertrophy in morbid obesity.

To determine the sensitivity and specificity of standard electrocardiographic criteria for left ventricular (LV) and right ventricular (RV) hypertrophy in morbid obesity, resting electrocardiograms and M-mode echocardiograms were obtained in 65 patients whose actual body weight was more than twice their ideal body weight and who were free from hypertension and organic heart disease not directly attributable to obesity. Electrocardiographic criteria for LV hypertrophy were tested using increased LV wall thickness, LV enlargement and increased LV mass (all determined echocardiographically) as diagnostic standards. Electrocardiographic criteria for RV hypertrophy were tested using echocardiographic RV enlargement or RV hypertrophy as a diagnostic standard. Sensitivity values for the electrocardiographic criteria for LV hypertrophy ranged from 0 to 13%, 0 to 20% and 0 to 12% using echocardiographic increased LV wall thickness, LV enlargement and increased LV mass, respectively, as diagnostic standards. Specificity values ranged from 73 to 100%, 87 to 100% and 83 to 100%, respectively, using these diagnostic standards. Sensitivity values for the electrocardiographic criteria for RV hypertrophy ranged from 0 to 16% and specificity values ranged from 95 to 100%. Combining electrocardiographic criteria within groups did not appreciably increase sensitivity and often decreased specificity to unacceptably low levels. The electrocardiogram is very limited in its ability to detect ventricular hypertrophy and chamber enlargement in morbidly obese patients.

Adult↗
PubMed1988

Effect of increasing intraabdominal pressure and volume on left ventricular function in continuous ambulatory peritoneal dialysis (CAPD).

To determine the effect of increasing intraabdominal pressure on left ventricular (LV) systolic function in patients undergoing continuous ambulatory peritoneal dialysis (CAPD), we studied 15 patients who had been on CAPD for at least 2 months. The study protocol included measurement of echocardiographic LV internal dimensions in diastole and systole, LV wall thickness and mass, LV ejection time, the mean velocity of circumferential fiber shortening (mean Vcf), heart rate, BP, and intraabdominal pressure. Measurements were obtained at baseline (OL) and following intraperitoneal infusion of 1-L increments of dialysate solution (up to 4 L) in both the recumbent and standing positions. Significant differences in LV systolic function resulting from intraperitoneal infusion of dialysate were confined to the subgroup with increased LV wall thickness (n = 8). In this subgroup, mean Vcf decreased progressively from 0.99 +/- 0.18 circumferences/second at baseline to 0.88 +/- 0.16 circumferences/second at 1 L (P = NS), to 0.86 +/- 0.16 circumferences/second at 2 L (P = NS), to 0.66 +/- 0.18 circumferences/second at 3 L (P less than 0.005), and to 0.60 +/- 0.14 circumferences/second at 4 L (P less than 0.005) in recumbent position. Measurements obtained in the standing position paralleled those observed during recumbency. These changes were accompanied by a significant decrease in the mean LV internal dimension in diastole and a significant increase in intraabdominal pressure, but no significant change in the mean LV internal dimensions in systole, mean heart rate, or mean systolic or diastolic BP.(ABSTRACT TRUNCATED AT 250 WORDS)

Abdomen↗
PubMed1988

Value and limitations of calcium channel blockade in the treatment of pulmonary hypertension associated with CREST--case reports.

Reversible vasospasm has been hypothesized to underlie the development of pulmonary hypertension in patients with CREST. Drugs that prevent arterial spasm have been used to treat pulmonary hypertension with variable results. The disparate pulmonary hemodynamic responses to calcium channel blockade reported herein suggest that CREST patients with mild pulmonary hypertension may have a component of reversible vasospasm responsive to vasodilator therapy, whereas patients with moderate to severe pulmonary hypertension may have fixed vessel lesions precluding a satisfactory response to calcium channel blockade.

Adult↗
PubMed1987

Pharmacotherapy of congestive heart failure. An evaluation of recent advances.

Vasodilator therapy represents an important step forward in the treatment of chronic left ventricular failure. Angiotensin converting enzyme (ACE) inhibitors appear to be the most versatile vasodilators, but selected direct-acting vasodilators, sympathetic inhibitors (prazosin), and possibly calcium channel antagonists (nifedipine and diltiazem) may be useful in certain situations. The bipyridine derivatives possess potent inotropic and vasodilating properties. The efficacy of intravenously administered amrinone and milrinone has been proven in the treatment of refractory left ventricular failure. Whether oral administration of milrinone or other bipyridine derivatives will prove to be safe and effective in the long-term treatment of chronic left ventricular failure remains uncertain.

Adrenergic alpha-Antagonists↗
PubMed1987

Comparative survival following permanent ventricular and dual-chamber pacing for patients with chronic symptomatic sinus node dysfunction with and without congestive heart failure.

To determine whether survival following permanent ventricular demand pacing differs from survival following permanent dual-chamber pacing in patients with symptomatic sinus node dysfunction (unexplained sinus bradycardia, subsidiary rhythms, sinus arrest, sinoatrial block, or the bradycardia/tachycardia syndrome), we followed 79 patients who received a VVI pacemaker (group 1) and 49 patients who received a DVI or DDD pacemaker (group 2) for 1 to 5 years. There was no significant difference in sex distribution, mean age, or the incidence of coronary heart disease, hypertension, valvular heart disease, diabetes mellitus, stroke, or renal failure between groups 1 and 2. Overall, the predicted cumulative survival rates at 1, 3, and 5 years were 89%, 82%, and 74%, respectively, for group 1 and 94%, 86%, and 78%, respectively, for group 2. In patients with preexistent congestive heart failure (CHF), predicted cumulative survival rates at 1, 3, and 5 years were 78%, 69%, and 57%, respectively, for group 1 (n = 23) and 90%, 83%, and 75%, respectively, for group 2 (n = 16). Five-year predicted cumulative survival was significantly lower in group 1 patients with CHF than in group 2 patients with CHF (p less than 0.03). There was no significant difference in 5-year cumulative survival rates between groups 1 and 2 in patients without CHF. The results suggest that permanent dual-chamber pacing enhances survival to a greater extent than permanent ventricular demand pacing in patients with chronic symptomatic sinus node dysfunction and CHF.

Aged↗
PubMed1987

Termination and suppression of multifocal atrial tachycardia with verapamil.

Multifocal atrial tachycardia (MAT) is an ectopic atrial tachyarrhythmia most commonly observed in very ill, elderly patients with hypoxia due to chronic pulmonary or cardiac disease. We have described a patient with recurrent MAT whose paroxysms of arrhythmia were promptly terminated with intravenous verapamil and were ultimately prevented by orally administered verapamil.

Administration, Oral↗
PubMed1987

Anomalous right coronary artery arising from the midportion of the left anterior descending coronary artery--case reports.

Although coronary artery anomalies are detected during 0.8-1.2% of routine adult cardiac catheterizations, anomalies of the right coronary artery are relatively uncommon and are generally of no clinical significance. This report focuses, however, on 2 patients whose RCA originated from the midportion of the left anterior descending artery, an anomaly with potentially important clinical implications, which are explored.

Aged↗
PubMed1987

Panic disorder: a frequent occurrence in patients with chest pain and normal coronary arteries.

From 10% to 20% of patients undergoing coronary arteriography for chest pain are subsequently found to have normal coronary arteries. We investigated the prevalence of panic disorder in these patients in a two-stage study. Our results indicate that approximately one third of patients with chest pain and angiographically normal coronary arteries have panic disorder. Proper diagnosis and treatment of these patients with panic disorder may be expected to substantially reduce their psychosocial morbidity.

Adult↗
PubMed1986

Effect of beta blockade with betaxolol on left ventricular systolic function in chronic stable angina pectoris and left ventricular dysfunction.

To assess the effect of beta blockade on left ventricular (LV) performance in patients with LV dysfunction and stable angina pectoris, 18 subjects taking a placebo followed by incremental doses of the cardioselective beta-adrenergic blocking agent betaxolol (5, 10, 20, 40 and 80 mg/day) were studied. The study ended with the achievement of optimal clinical beta blockade (heart rate at rest 50 to 60 beats/min, a 20% or smaller increase in heart rate during stage 1 of symptom-limited treadmill exercise using the modified Bruce protocol). Optimal clinical beta blockade produced a decrease in mean frequency of angina, from 6.8 +/- 1.7 to 0.7 +/- 0.8 episodes per week (p less than 0.0005) and an increase in mean treadmill exercise capacity, from 3.1 +/- 1.7 to 7.7 +/- 2.8 minutes (p less than 0.0005). LV systolic function was assessed at rest and during symptom-limited exercise with radionuclide left ventriculography. Mean LV ejection fraction (EF) during therapy with placebo was 39 +/- 7% at rest and 40 +/- 8% at peak exercise. Mean LVEF during optimal clinical beta blockade was 43 +/- 11% at rest and 45 +/- 10% at peak exercise. Neither of these changes was statistically significant. No patient had clinical or radiographic signs of LV failure. The results suggest that optimal clinical beta blockade with betaxolol, in doses sufficient to significantly reduce the frequency of angina and improve exercise capacity in patients with stable angina pectoris and mild to moderate LV systolic dysfunction, does not cause significant deterioration of LV systolic function or produce LV failure.

Adrenergic beta-Antagonists↗
PubMed1986

Comparative cardiac effects of hemodialysis and continuous ambulatory peritoneal dialysis.

To assess the comparative cardiac effects of hemodialysis and continuous ambulatory peritoneal dialysis (CAPD), we performed M-mode echocardiography prior to and immediately following hemodialysis on 56 patients and during the dwell phase of CAPD on 39 patients. Hemodialysis produced a significant increase in the mean velocity of circumferential fiber shortening (VCF, an index of left ventricular systolic function) in patients with low VCF prior to dialysis, but resulted in no significant change in VCF in patients with normal predialysis VCF. Hemodialysis produced a significant increase in VCF in patients with a normal predialysis left ventricular end-diastolic volume index (LVEDVI), but resulted in no significant change in VCF in patients with left ventricular dilatation prior to dialysis. Hemodialysis produced a significant decrease in mean LVEDVI and mean stroke index, but resulted in no significant change in mean cardiac index due to a reflex increase in heart rate. Mean LVEDVI, mean stroke index, and VCF values in patients on CAPD were not significantly different from those observed immediately following hemodialysis. Mean cardiac index and mean heart rate were significantly lower in CAPD patients than in posthemodialysis patients. Pericardial effusion was observed in 25% of hemodialysis patients and 5% of CAPD patients (p less than 0.05). We conclude (1) the effects of hemodialysis on left ventricular performance are variable and depend in part on predialysis left ventricular volume and left ventricular systolic function, (2) except for a lower cardiac index, left ventricular hemodynamics for CAPD patients resemble those of posthemodialysis patients, and (3) pericardial effusion occurs with significantly higher frequency in patients on hemodialysis than in those on CAPD.

Cardiac Output↗
PubMed1986

Observer variation in the echocardiographic diagnosis of mitral valve prolapse.

To assess inter- and intraobserver variation in the echocardiographic diagnosis of mitral valve prolapse, three independent observers analyzed M-mode echocardiograms (n = 80) and two-dimensional echocardiograms (n = 65) of patients with a mobile midsystolic click with or without a late or holosystolic murmur. In addition, a control group of 100 normal echocardiograms were interspersed among the echocardiograms of patients with mitral valve prolapse and were then interpreted. Each of the three observers analyzed all M-mode and two-dimensional echocardiograms initially and then 2 weeks later for the presence or absence of mitral valve prolapse. M-mode echocardiographic criteria for mitral valve prolapse consisted of late systolic posterior motion (greater than or equal to 3 mm) of one or both mitral leaflets or holosystolic hammocking (greater than or equal to 3 mm) of one or both mitral leaflets. Two-dimensional echocardiographic criteria for mitral valve prolapse consisted of: posterior systolic arching of one or both mitral leaflets in the parasternal long-axis view, and/or posterior systolic bowing of one or both mitral leaflets in the apical four-chamber view posterior to the plane of the mitral anulus, and/or excessive posterior coaptation of the mitral leaflets in either view flush with or posterior to the plane of the mitral anulus. There was insignificant observer variation both in the M-mode and two-dimensional echo groups, as determined using Cochran's Q test.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗