Antone F. Salel

Effects of diltiazem on serum lipids, exercise performance and blood pressure: Randomized, double-blind, placebo-controlled evaluation for systemic hypertension

Treatment of hypertension with diuretics, beta blockers and alpha blockers may be associated with adverse effects on exercise performance, serum lipids and blood chemistries, as well as with orthostatic effects and fluid retention. A randomized, double-blind, placebo-controlled trial of a sustained-release preparation of diltiazem as sole therapy for moderate essential hypertension was conducted. Diltiazem was administered 2 times a day (360 mg/day) to 16 patients and placebo to 14 patients in a 12-week study. Average supine blood pressure with diltiazem therapy fell from 161/100 to 144/87 mm Hg without fluid retention or orthostatic effects. In an open-label study, patients from the placebo and diltiazem groups continued with diltiazem therapy. At an average of over 8 months, supine blood pressure on diltiazem was 147/88 mm Hg, and after withdrawal to single-blind placebo, average supine blood pressure increased to 173/104 mm Hg. All changes were significant compared with baseline and placebo (p less than 0.01). On diltiazem therapy, maximal treadmill exercise was increased by an average of 55 seconds (p less than 0.01), whereas heart rate, blood pressure and double product (heart rate X blood pressure) were reduced at submaximal exercise, and heart rate and double product were reduced at maximal exercise. No changes in serum glucose, potassium or uric acid were found. No adverse effects on serum lipids occurred. Diltiazem treatment was associated with an increase in high-density lipoprotein cholesterol (52 to 60 mg/dl, p less than 0.006) and a decrease in total cholesterol:high-density lipoprotein cholesterol ratio (4.7 to 4.2, p less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

Afterload reduction therapy with nitroprusside in severe aortic regurgitation: Improved cardiac performance and reduced regurgitant volume

To assess the hemodynamic effects of afterload reduction in severe aortic regurgitation, nitroprusside was infused at cardiac catheterization in 12 patients with aortic regurgitation. Cardiac hemodynamics, angiographic variables and regurgitant volumes were quantified during control periods, and nitroprusside was infused to reduce systemic systolic pressure to 110 to 125 mm Hg. The following were reduced by the drug: systolic arterial pressure (from 154 +/- 6.4 to 115 +/- 2.3 mm Hg, P less than 0.001); left ventricular end-diastolic pressure (from 23 +/- 2.2 to 11 +/- 1.0 mm Hg, P less than 0.001); systemic vascular resistance (from 1,782 +/- 133 to 1,148 +/- 94 dynes sec cm-5, P less than 0.001); left ventricular end-diastolic volume (from 242 +/- 25 to 196 +/- 19 ml, P less than 0.001); aortic regurgitant fraction (from 0.53 +/- 0.05 to 0.44 +/- 0.06, P less than 0.01); and aortic regurgitant minute volume (from 5.5 +/- 0.10 to 4.3 +/- 0.09 liters/min, P less than 0.01). Effective cardiac index increased (from 2.49 +/- 0.19 to 3.10 +/- 0.24 liters/min per m2, P less than 0.01), and left ventricular ejection fraction rose (from 0.55 +/- 0.03 to 0.61 +/- 0.03, P less than 0.005). These data indicate that afterload reduction with nitroprusside in severe aortic regurgitation improves cardiac performance, greatly decreases left ventricular preload and reduces aortic regurgitant volume. Thus, nitroprusside therapy has special value in severe aortic regurgitation that is of particular benefit in critical clinical conditions.

Chronic stable inferior myocardial infarction: unsuspected harbinger of high-risk proximal left coronary arterial obstruction amenable to surgical revascularization.

Eighty-four patients with previous uncomplicated isolated inferior myocardial infarction underwent coronary arteriography to determine the prevalence and distribution of coronary stenoses in order to identify those patients at high risk for early death. Coronary risk factors and treadmill stress testing were evaluated as predictors of left coronary artery disease, and the clinical course was compared of patients undergoing coronary bypass surgery versus those treated medically. Of the 84 patients, 17 (20 percent) had one vessel stenosis (75 percent or more luminal narrowing), 29 (35 percent) had stenosis of two and 38 (45 percent) had stenosis of all three major coronary arteries. Fifty-three patients (63 percent) had stenosis of the proximal left anterior descending coronary artery including 8 with complete and 18 with subtotal occlusion. Of the 53 patients with proximal left anterior descending arterial stenosis, 42 (79 percent) had an operable condition (no distal obstruction) as did 36 (69 percent) of 52 with circumflex arterial stenosis. Although the presence of multiple coronary risk factors, particularly with a positive stress test, was predictive of multivessel stenosis, lack of risk factors and a negative exercise test were nonspecific. Of 45 patients followed up for 18 months, 14 who underwent, coronary bypass surgery were compared with 31 medically treated patients with similar cardiac function and coronary pathoanatomy. Ten surgically treated patients (71 percent) had reduced angina compared with nine medically treated patients (29 percent) ( P P P > 0.05). Thus, serious left coronary artery disease is highly prevalent as well as operable in patients with chronic inferior myocardial infarction. The latter condition thereby provides a clinically useful and sensitive marker of high risk coronary arterial stenosis.

Echography and Phonography of Acute Aortic Regurgitation in Bacterial Endocarditis

Since management of acute aortic regurgitation in bacterial endocarditis is enhanced by early recognition, echocardiography and phonocardiography were evaluated in three such cases documented by catheterization and surgery without positive blood cultures and compared to echophonograms of 34 patients with aortic regurgitation of other origins. Endocarditis manifested distinctive, thickened, irregular aortic leaflet echoes with normal systolic excursion and mitral echopreclosure with anterior leaflet fluttering. Mitral preclosure resulted in mid- or end-diastolic crescendo murmur accompanied by soft first heart sound. Aortic echograms in nonendocarditis showed either widened root, diminished leaflet excursion, absence of irregular valvular thickening, or normal leaflets, all without mitral preclosure. This study shows specific echophonographic findings of aortic regurgitation due to endocarditis that enable diagnosis of this condition in the absence of positive blood cultures.

An apolipoprotein preferentially enriched in cholesteryl ester-rich very low density lipoproteins☆

Abstract One of the plasma apolipoproteins, rich in arginine and predominantly alpha-helical in conformation, is preferentially enriched in cholesteryl ester-rich very low density lipoproteins. The incidence of plasma lipoproteins that are enriched in the arginine-rich apolipoprotein appears to be a function of genetic, hormonal, and dietary factors and is high in hypothyroidism and type III hyperlipoproteinemia and in rabbits fed excess cholesterol. This apolipoprotein appears to be one of several involved primarily in the transport and metabolism of cholesteryl esters and/or cholesterol.

New approach to interpretation of technetium-99m pyrophosphate scintigraphy in detection of acute myocardial infarction: Clinical assessment of diagnostic accuracy

A modified classification for interpreting technetium-99m pyrophosphate scintigrams defines the 2+ diffuse pattern of tracer uptake as equlvocal rather than positive for acute myocardial infarction. Results of scintigraphy using this classification were compared with results of standard diagnostic tests for myocardial infarction in 235 patients admitted to a coronary care unit with acute chest pain. Of 81 patients with acute transmural infarction by standard clinical, electrocardiographic and serum enzyme criteria, 76 had a positive, 5 an equivocal and none a negative scintigram. Of 18 with acute nontransmural infarction by standard criteria, 7 had a positive, 9 an equivocal and 2 a negative scintigram. This it was uncommon for a patient with acute myocardial infarction, transmural or nontransmural, to have a definitely negative technetium-99m pyrophosphate study. Ten patients had equivocal evidence of infarction by standard criteria. Of the remaining 126 patients with no evidence of acute myocardial infarction by standard criteria, 87 had a negative, 35 an equivocal and 4 a definitely positive scintigram. Thus the definitely positive scintigraphic pattern was relatively highly specific for acute myocardial infarction. If the 2+ pattern had been considered positive, the specificity of the technique would have been greatly decreased. Computer processing strengthened observer certainty of the visual impression but changed the scintigraphic evaluation in only eight cases. Thus, use of an equivocal pattern renders technetium-99m pyrophosphate imaging both an extremely sensitive and specific method for detecting acute myocardial infarction.

Radionuclide assessment of nitroglycerin influence on abnormal left ventricular segmental contraction in patients with coronary heart disease.

Noninvasive gated cardiac blood pool imaging with technetium-99m autologous erythrocytes was employed to differentiate reversible versus irreversible abnormal ventricular segmental contraction by regional wall and pump responses to sublingual nitroglycerin in 25 patients with chronic coronary heart disease. In 12 patients without ECG infarctions compared to 13 with infarctions, radioisotopic images demonstrated significantly greater percent decreases in end-systolic volumes (33.8 ± 6.7 SEM VS 18.7 ± 4.4; P ⩽ 0.05) without differences in percent reductions in end-diastolic volumes (13.7 ± 3.9 vs 11.6 ± 6.1; NS) and thereby significantly greater percent increases in ejection fractions (9.3 ± 1.6 vs 4.1 ± 2.0; P ⩽ 0.05). In the 22 patients with regional dyssynergy, improvement in disordered pattern and extent of localized dyssynergy following antianginal action of nitroglycerin was related to ECG absence of prior infarction. These observations demonstrate the clinical accuracy of atraumatic scintigraphy in the detection of reversible localized dyssynergy due to myocardial ischemia in coronary heart disease.

Noninvasive detection of regional myocardial ischemia using rubidium-81 and the scintillation camera: comparison with stress electrocardiography in patients with arteriographically documented coronary stenosis.

The sensitivity of rest and stress myocardial perfusion studies using scintillation camera imaging of intravenously administered rubidium-81 (81Rb) in the detection of myocardial ischemia was compared to that of stress electrocardiography by relating results in 40 patients to the degree of stenosis delineated by coronary arteriography. Of 33 patients with greater than 75% stenosis of at least one of the three major coronary vessels (significant stenosis), rest and stress 8lRb imaging detected ventricular ischemia in 29 (88%), whereas simultaneous stress electrocardiography was positive (1 mm or greater horizontal ST-segment depression) in only 19 (58%) of the same patients. Five of the 29 patients who developed stress-induced scintigraphic evidence of ischemia did not develop angina or a positive electrocardiogram with stress. In 31 of the 33 patients with significant coronary stenosis, either the stress scintigram or the stress electrocardiogram was positive. In seven patients with less than 50% narrowing of a major coronary vessel on coronary arteriography, the stress scintigrams were negative, whereas the stress electrocardiograms were positive in the two of these patients with the syndrome of angina with normal coronary arteriograms. It is concluded that high resolution images of the myocardium can be obtained with 81Rb using the scintillation camera with special shielding, and that rest and stress 81Rb scintigraphy appears to provide greater sensitivity and specificity when compared to stress electrocardiography in the noninvasive identification of significant coronary stenosis.

The importance of type IV hyperlipoproteinemia as a predisposing factor in coronary artery disease

Abstract One hundred seventy-six consecutive patients were evaluated for the frequency of potentially reversible risk factors associated with coronary artery disease. The results In a group of 105 patients with objective coronary artery disease was compared with a control group of 71 patients without coronary disease. The prevalence of risk factors was examined in the entire group of 176 patients and in a young subgroup of 55 patients with coronary disease who were under 50 years of age. Obesity was the most prevalent risk factor for the whole group but was especially significant for the young patient with coronary disease. Type IV hyperlipoproteinemia, the most prevalent lipoprotein disorder in the study, was significantly elevated in the entire group as well as in the young patients with coronary disease. An abnormal glucose tolerance test was another feature of the young patients with coronary disease. Although some men with coronary disease did not have a predisposing metabolic abnormality, no woman in the study had coronary disease if a metabolic abnormality was not present. These findings emphasize the metabolic nature of coronary artery disease as well as the atherogenic potential of type IV hyperlipoproteinemia.

Accuracy of numerical coronary profile. Correlation of risk factors with arteriographically documented severity of atherosclerosis.

We compared a coronary risk profile (developed by the Framingham Study) based on age, sex, cigarette smoking, glucose intolerance, left ventricular hypertrophy, systolic blood pressure and serum cholesterol to angiographically determined severity of coronary-artery disease in 158 consecutive patients undergoing cardiac catheterization. A profile of 1.0 indicated average relative risk. Risk profiles for 105 patients with angiographically documented coronary-artery disease was 1.52 whereas it was 1.08 for the group without coronary disease (P less than 0.01). There was no difference between the patients with coronary disease with (1.44) and those without previous infarct (1.46). The coronary risk profile, however, increased with increasing severity of coronary disease. The high-risk coronary patient can be identified by seven easily measured risk factors, and the extent of coronary-artery disease increases with the number and severity coronary risk factors.