Joe L. Rod

Evaluation of the beta-blocking drug acebutolol in angina pectoris

The effects of the beta-adernergic blocking drug acebutolol were studied in 23 patients with angina pectoris and angiographically documented coronary artery disease. Patients were evaluated clinically, by graded treadmill testing and by 24-hour Holter monitoring in the control state, after 2 weeks treatment with placebo, and after 2 weeks treatment with 600 mg. and then 1,200 mg. of acebutolol. Acebutolol (in a daily dose of 600 mg.) was an effective antianginal drug: the number of clinical attacks of angina pectoris (p less than 0.001) and the consumption of sublingual nitrate decreased (p less than 0.01), there was a significant increase in the treadmill effort tolerance as measured by the time to appearance of ischemic ECG changes (p less than 0.001) and the total work performed (p less than 0.001), and there was also a significant decrease in ischemic ST segment depression on 24-hour Holter monitoring. Treatment with 1,200 mg. acebutolol was associated with a further decrease in heart rate and a further improvement in effort tolerance on treadmill testing (p less than 0.05). On the large dose of the drug, however, there was no further clinical improvement, and no further improvement on 24-hour ECG monitoring; several patients complained of weakness and fatigue. Graded treadmill testing was an excellent objective method for assessing physical effort tolerance and its improvement after treatment with the beta-blocking drug. Twenty-four-hour Holter monitoring was a useful and complementary test, especially in patients who stopped exercising on the treadmill because of fatigue or weakness, and especially for assessing the efficacy of beta-blockade in controlling emotionally induced tachycardia and ischemia in the patients own daily environment.

Importance of immediate and very early postprocedural angiographic and thallium-201 single photon emission computed tomographic perfusion measurements in predicting late results after coronary intervention

We examined prospectively the hypothesis that the adequacy of initial dilatation may be a major determinant of the late result of coronary angioplasty and that a better assessment of initial dilatation can be made from a combined angiographic and perfusion study than from angiography alone. Angiographic and perfusion (thallium-201 single-photon-emission computed tomography) measurements were made very early (18 to 24 hours) after coronary angioplasty in 59 patients (67 lesions) and also immediately (37 +/- 16 minutes) after the procedures in 19 of them (23 lesions). The early measurements, singly, in combination, and as a restenosis index (restenosis index = thallium-201 ischemic score (units) - minimal luminal area (squared millimeters) were examined as predictors of the late angiographic result. At late angiography (5.5 +/- 2.2 months after angioplasty), residual stenosis was related to the immediate and very early postangioplasty minimal luminal dimension, thallium-201 ischemic score, and restenosis index, and also to day-1 loss and lesion length. The combination of a normal result in the immediate or early thallium-201 perfusion study with a large ( > or = 2 mm) angiographic luminal dimension stratified a group of patients with better long-term results after angioplasty and a lower incidence of late restenosis (p = 0.03). The findings emphasize the importance of the initial procedure as a determinant of the late result of angioplasty.

Early Calcification and Obstruction of a Mitral Porcine Bioprosthesis

A patient is described in whom severe prosthetic valvular stenosis developed ten months after mitral valve replacement with an Angell-Shiley porcine heterograft. At emergency operation, calcification of the prosthesis was revealed. Early calcification and stenosis of a porcine heterograft valve is a life-threatening complication that must be recognized promptly and treated by emergency valve replacement.

Evaluation of functional capacity during exercise radionuclide angiography

This study compared functional capacity during treadmill exercise testing and during bicycle exercise radionuclide angiography. 262 patients performed maximal upright bicycle exercise and also performed maximal graded exercise testing using either the Bruce (n = 158) or Naughton (n = 104) treadmill protocols. The functional capacity was well correlated between bicycle and treadmill for Bruce (r = 0.89), Naughton (r = 0.93), or combined treadmill (r = 0.90) protocols. However, the functional capacity was significantly lower during bicycle than during treadmill testing for Bruce (8.3 vs. 10.5 METs), Naughton (7.8 vs. 8.7 METs), or combined treadmill (8.1 vs. 9.8 METs) protocols. Treadmill functional capacity could be predicted from bicycle functional capacity using the following equations: Bruce METs = 1.00 X (bike METs) + 2.23, Naughton METs = 0.94 X (bike METs) + 1.40, and combined treadmill METs = 0.98 X (bike METs) + 1.85.