Virendra S. Mathur

Surgical treatment for stable angina pectoris. Prospective randomized study.

To evaluate the role of coronary bypass treatment of stable angina, 72 patients were randomly divided into surgical and medical groups. They were followed with treadmill tests and repeat catheterization. Anginal symptoms decreased or disappeared in 89 per cent of those operated on and 65 per cent of those not operated on, but more of the former than of the latter became asymptomatic: 69 vs. 11 per cent respectively (p smaller than 0.01). Exercise tolerance time improved significantly (p smaller than 0.001) in both groups, but more in the group operated on, plus 78 per cent vs. plus 48 per cent, p smaller than 0.05. During a 28-month follow-up period, fewer cardiac complications occurred in the patients operated on--14 vs. 34 (p smaller than 0.02). Mortality was 9 per cent in the patients operated on and 14 per cent in those not operated on; this difference is not significant. The results indicate that improvement, though demonstrable in both groups, is greater with surgery, and quality of life during the first 28 months is better in patients who are operated on.

Restenosis after transluminal coronary angioplasty detected with exercise-gated radionuclide ventriculography

Forty-one patients were evaluated with exercise-gated radionuclide ventriculography before and within 4 days after successful transluminal coronary angioplasty and 4 to 12 months later. Patients were subgrouped according to the degree of restenosis demonstrated angiographically at 4 to 12 months (Group I [n = 23]: less than or equal to 20%; Group II [n = 10]: greater than 20% but less than 50%; Group III [n = 8]: greater than or equal to 50%). Patients with abnormal findings on gated radionuclide ventriculography (less than 5 point increase in ejection fraction or wall motion deterioration) early after angioplasty were eventually found to have a greater degree of restenosis than were patients with normal findings (41.2 +/- 30.3 versus 19.0 +/- 25.4% restenosis, p less than 0.0001). The accuracy of abnormal radionuclide ventriculography in predicting 50% or greater restenosis was 73% immediately after angioplasty and 77% at the time of follow-up angiography. Gated radionuclide ventriculographic results were abnormal in 5% of Group I patients compared with 75% of Group III patients (p less than 0.01) early after angioplasty; at late follow-up, they were abnormal in 27% of Group I patients compared with 88% of Group III patients (p less than 0.01). Group I patients had a greater increase in ejection fraction than did Group III patients at early (+11.3 +/- 7.5 versus + 3.5 +/- 6.5 points, p less than 0.01) and late (+11.8 +/- 7.8 versus -1.9 +/- 8.7 points, p less than 0.0005) follow-up. It is concluded that gated radionuclide ventriculography is useful in predicting coronary restenosis after transluminal coronary angioplasty.

Complete Heart Block Induced During Cardiac Catheterization of Patients with Pre-existent Bundle-Branch Block The Hazard of Bilateral Bundle-Branch Block

The hazard of complete atrioventricular block during cardiac catheterization of patients with pre-existent bundle-branch block is described. A catheter-induced bundle-branch block, during catheterization of the ventricle opposite that which was already the site of bundle-branch block, would produce complete heart block in the form of bilateral bundle-branch block. Five patients in whom this complication occurred are described.

Coronary artery bypass in the elderly

Coronary artery bypass is being performed with increasing frequency in various subsets of patients who appear to be at an increased native risk from their disease. The elderly patient who has coronary artery disease is one of the subsets which appears to carry an increased operative risk. Our institution’s interest in elderly surgical patients span for more than two decades as evidenced by earlier reports [1–3]. Several recent studies have shown that the advances in all phases of coronary care contribute immensely to the application of coronary bypass in the elderly with gratifying surgical results [4–13]. This study presents our experience with consecutive elderly patients who underwent coronary artery bypass alone from 1970 to 1983.

Clinical standardization of the new dual cardiac probe.

A new mobile dual cardiac probe has been introduced for measurements of the left ventricular ejection fraction (LVEF). In 28 patients, correlation between LVEFs measured by the dual probe and biplane contrast ventriculography was 0.83. Central and peripheral injections yielded comparable curves, and the resultant LVEFs correlated well (R = 0.95). Correlation between LFEVs determined by the probe and by gated blood pool imaging in 43 patients was also 0.83. In 21 patients given three serial injections of 99mTc-albumin, the mean variation of the ejection fraction was 4.2 +/- 3.2%; however, reproducibility was unsatisfactory using 99mTc-sulfur colloid due to sequestration in hepatic background tissue.

The clinical significance of atrial pacing-induced Mobitz i atrioventricular block in patients with coronary artery disease

Two hundred consecutive patients with a history of chest pain undergoing cardiac catheterization, coronary angiography and atrial pacing have been analyzed to assess the clinical significance of Mobitz I atrioventricular (A-V) block developing with the stress of atrial pacing. Of 160 patients with coronary artery disease, 26 (16%) developed Mobitz I A-V block at rates below 140 beats/min. Eighteen of these 26 patients (69%) had electrocardiographic evidence of old inferior wall myocardial infarction, compared to only 34 of the remaining 134 patients (29%) (P = less than 0.01). During the mean follow-up of 29.5 months (range 18-50 months) none of the 26 patients has developed spontaneous second or third degree A-V block. Twenty-three of the 26 patients had an exercise test within one week of the pacing study. No A-V block was noticed during or immediately following exercise, although the mean heart rate attained during exercise was higher than the mean pacing rate at which the A-V block occurred (136 +/- 5 vs 122 +/- 3, P = less than 0.01). Eighteen of these 23 achieved heart rates equal to or higher than the pacing rate at which A-V block developed. Nineteen (83%) shortened their P-R interval during exercise and 4 (17%) did not change the P-R length. Although atrial pacing-induced Mobitz I A-V block may indicate a latent A-V nodal conduction abnormality in some cases, its demonstration does not necessarily predict the occurrence of spontaneous advanced A-V block. Exercise should not be restricted in these patients on the basis of such a finding during a pacing study.

Vectorcardiographic differentiation between right ventricular hypertrophy and posterobasal myocardial infarction

Vectorcardiograms were recorded by the Frank lead system in 203 cases of right ventricular hypertrophy (RVH) and 85 cases of posterobasal myocardial infarction (PBMI). Of the RVH cases, 33 were confirmed by autopsy and 135 by cardiac catheterization or surgery. Of the cases of PBMI, 12 were confirmed by autopsy and 48 had definite clinical episodes associated with enzymatic or serial electrocardiographic changes or both.Of several measurements made, the following proved most helpful: (1) location of mean frontal plane QRS axis between 75° and 220° in 64% of the cases of RVH and between 350° and 74° in 78% of the cases of PBMI; (2) location of mean horizontal plane QRS axis between 350° and 90° in 85% of the cases of PBMI but in only 11% of the cases of RVH; (3) location of the 0.04-sec instantaneous vector in the horizontal plane between 350° and 60° in 76% of the cases of PBMI but in only 22% of the cases of RVH; (4) magnitude of terminal rightward voltage of less than 1.0 mv in 88% of the cases of PBMI and equal to or greater than 1.0 mv in 80% of the cases of RVH; and (5) clockwise inscription of the horizontal plane loop favored RVH, but counterclockwise rotation in the horizontal plane was not helpful. Synthesis of criteria 2 and 4 provided the best combination for the separation of RVH from PBMI. If both these criteria were fulfilled, a correct diagnosis could be made with 95% certainty.

Prospective Randomized Study of Coronary Artery Disease: Nine Year Follow-up

ABSTRACT A randomized prospective study of coronary artery bypass surgery was started in 1972. A total of 116 patients with stable angina and operable critical coronary disease were entered into th...