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D A Weiner

Publications and source records attributed to D A Weiner.

13 recordsLinked to original sources

Significance of silent myocardial ischemia after coronary artery bypass surgery.

The prevalence and prognostic significance of transient myocardial ischemia after coronary artery bypass grafting (CABG) were evaluated. In 3 studies, ischemia was found in an average of 24% of patients by ambulatory electrocardiographic monitoring at 3-12 months after CABG. An average of 36% of patients in 3 other studies experienced ischemic ST-segment depression during exercise testing at 4-50 months after CABG. Of the ischemic episodes, 77% were silent during exercise testing. In the Coronary Artery Surgery Study (CASS) randomized patient subsets, survival at 12 years was significantly lower for patients who had either silent or symptomatic ischemia during exercise testing at 6 months after CABG compared with those who had no ischemia.

Coronary Artery Bypass

Safety and clinical use of exercise testing one to three days after percutaneous transluminal coronary angioplasty.

To evaluate both the safety and clinical use of predischarge symptom-limited exercise testing after successful uncomplicated percutaneous transluminal coronary angioplasty (PTCA), 100 patients were randomized to undergo exercise testing (n = 50) or no exercise testing (n = 50). There were no differences in clinical or angiographic characteristics between the groups. Exercise testing was performed 38 +/- 14 hours after PTCA. Patients who exercised achieved 71 +/- 12% of predicted maximal heart rate, with 38% reaching greater than or equal to stage III of the Bruce protocol. No patient in either group developed cardiac complications during 48-hour follow-up. Of the 11 patients with a positive test result, 92% had angiographically incomplete revascularization. Attending physicians (n = 16) were questioned both before and after exercise testing about when, after discharge, they would allow their patient to perform each of 11 specific activities of daily living. Questionnaires were administered to physicians at similar time frames for patients in the no-exercise group. Comparison of the responses between initial and repeat questionnaires showed that patients in the exercise group (with a test result negative for ischemia) were allowed to perform 7 of 11 activities, including return to work, earlier (p less than 0.05) than the no-exercise patients. These data indicate that in this well-defined group of patients, symptom-limited exercise testing early after PTCA appears to be safe, and alters physician management in allowing patients with a negative test result to return to various activities at an earlier date. Such testing may be useful in counseling patients after PTCA.

Activities of Daily Living

Comparison of the clinical profile and outcome of women and men in cardiac rehabilitation.

Few data are available regarding the outcome of women in cardiac rehabilitation. To determine whether women differ from men in clinical profile and outcome, 225 consecutive patients were prospectively evaluated in an urban, multidisciplinary, exercise-based cardiac rehabilitation program. Among the 51 women (age 56 +/- 10) and 174 men (age 54 +/- 10), most were: white (84%), married (64%), employed (63%), had had myocardial infarction or revascularization, or both (66%), and traveled less than 10 miles to the program (92%). Risk profiles revealed obesity in 48% (mean Metropolitan Relative Weight = 124 +/- 22%), hypertension in 47%, smoking in 23%, diabetes in 16%, and mean cholesterol of 236 +/- 45 mg/dl. Compared with men, more women were nonwhite, unemployed, unmarried, hypertensive or diabetic (p less than 0.0001) and had higher cholesterol (p less than 0.01). Compliance rates were similar for women (51%) and men (63%) (p = not significant). Univariate predictors of program noncompliance differed between women and men. Initial exercise capacity was less for women than for men, but both groups achieved a similar training effect. Women increased their exercise time by 31% and peak METs by 30%, whereas men showed a 21% increase in exercise time and 16% increase in peak METs achieved (p less than 0.001). Thus, in this cardiac rehabilitation program, women have a less favorable risk factor profile and differ from men with regard to baseline demographics and predictors of program completion. Women, however, have similar rates of compliance and achieve the same improvement in functional capacity with training.

Adult

Comparison of ischemic and physiologic responses during exercise tests in men using the standard and modified Bruce protocols.

The importance of low-level (warm-up) exercise for reducing exercise-induced myocardial ischemic symptoms in patients with coronary artery disease is well-recognized by clinicians. Whether altering the abruptness of exercise, such as that which occurs during different frequently used testing protocols, affects myocardial ischemic variables and maximal exercise capacity has not been resolved. This study seeks to determine the effects of altering the increment of work-rate change per exercise stage on both the ischemic threshold and maximal exercise capacity using 2 frequently used exercise testing protocols. Thirty-two patients with documented coronary artery disease and previously positive exercise tests (ischemic ST depression greater than or equal to 1.0 mm) performed symptom-limited exercise tests using both the standard and modified Bruce protocols in random order, 1 hour apart. Exercise electrocardiograms were analyzed to determine the ischemic threshold, defined as heart rate at onset of greater than or equal to 1.0 mm ischemic ST depression. Patients achieved a higher peak heart rate (124 +/- 19 vs 117 +/- 21 beats/min; p less than 0.0001), rate-pressure product (21.4 +/- 3.9 vs 19.8 +/- 4.1 beats/min x mm Hg x 10(3); p less than or equal to 0.0001) and oxygen consumption (VO2) (18.5 +/- 3.7 vs 16.5 +/- 4.4 ml/kg/min; p less than or equal to 0.001) with the standard than with the modified Bruce protocol. At matched submaximal exercise stages there were no differences in VO2, heart rate or oxygen pulse between protocols. Time to ischemic threshold was significantly reduced with the standard compared with the modified Bruce protocol (312 +/- 107 vs 607 +/- 221 seconds; p less than 0.0001).(ABSTRACT TRUNCATED AT 250 WORDS)

Aged

Significance of silent myocardial ischemia during exercise testing in patients with diabetes mellitus: a report from the Coronary Artery Surgery Study (CASS) Registry.

To evaluate the significance of ischemic ST depression without anginal chest pain during exercise testing among patients with diabetes mellitus, the data on 45 such patients from the Coronary Artery Surgery Study registry were analyzed. These patients (group 1, silent ischemia) were compared with 37 diabetic patients with both ischemic ST depression and chest pain (group 2, symptomatic ischemia), with 31 diabetic patients without ischemic ST depression or chest pain (group 3, no ischemia), and with 429 patients without diabetes who had silent ischemia during exercise testing. All patients had documented coronary artery disease (CAD) (greater than 70% diameter narrowing). The 6-year survival among patients with silent ischemia was worse in diabetic than nondiabetic patients (59 vs 82%, respectively, p less than 0.001). By contrast, the 6-year survival among patients without ischemia was similar among diabetic and nondiabetic patients (93 vs 85%, respectively, p = 0.476). Among diabetic patients, survival at 6 years with medical treatment was 59% for group 1, 66% for group 2 and 93% for group 3 (p = 0.008). Survival among subsets of patients with diabetes and silent ischemia (group 1) based on the extent of CAD and left ventricular function ranged from 100 to 32% (p = 0.093). The survival of the 45 patients with diabetes mellitus and silent ischemia (group 1) treated medically was compared with that of 28 patients receiving coronary artery graft bypass surgery.(ABSTRACT TRUNCATED AT 250 WORDS)

Coronary Artery Bypass

Prevalence and prognostic significance of silent and symptomatic ischemia after coronary bypass surgery: a report from the Coronary Artery Surgery Study (CASS) randomized population.

The prevalence and prognostic significance of postoperative myocardial ischemia, as detected by exercise testing, were prospectively assessed in 174 patients from the Coronary Artery Surgery Study (CASS) randomized surgical population who had exercise testing before and 6 months after coronary artery bypass graft surgery. Whereas the prevalence of symptomatic ischemia significantly decreased postoperatively (52% vs. 6%, p less than 0.001), the frequency of silent myocardial ischemia did not change (30% vs. 29%). Survival at 12 years after bypass surgery based on the 6-month postoperative exercise test results was significantly better for the 112 patients with no ischemia (80%) than for the 51 patients with silent ischemia (68%) or the 11 patients with symptomatic ischemia (45%). These data show that coronary artery bypass graft surgery diminishes the overall prevalence of symptomatic but not silent ischemia and that both silent and symptomatic ischemia adversely affect the postoperative prognosis of these patients.

Coronary Artery Bypass

Risk stratification in angina pectoris.

Risk stratification of the patient with angina pectoris can be accomplished initially by the history, physical examination, and resting electrocardiogram. Noninvasive testing can add important prognostic information and identify patients who might benefit from revascularization procedures. An exercise electrocardiographic test usually is the initial test to determine risk, but exercise 201Th scintigraphy and exercise radionuclide angiography can provide important additional information regarding outcome in selected subsets of patients.

Angina Pectoris

Exercise stress testing. Correlations among history of angina, ST-segment response and prevalence of coronary-artery disease in the Coronary Artery Surgery Study (CASS).

To determine to what extent the diagnostic accuracy of stress testing is influenced by the prevalence of coronary-artery disease, we correlated the description of chest pain, the result of stress testing and the results of coronary arteriography in 1465 men and 580 women from a multicentered clinical trial. The pre-test risk (prevalence of coronary-artery disease) varied from 7 to 87 per cent, depending on sex and classification of chest pain. A positive stress test increased the pre-test risk by only 6 to 20 per cent, whereas a negative test decreased the risk by only 2 to 28 per cent. Aothough the percentage of false-positive results differed between men and women (12 +/- 1 per cent versus 53 +/- 3 per cent P less than 0.001), this difference was not seen in a subgroup matched for prevalence of coronary-artery disease. We conclude that the ability of stress testing to predict coronary-artery disease is limited in a heterogeneous population in which the prevalence of disease can be estimated through classification of chest pain and the sex of the patient.

Angina Pectoris

The predictive value of anginal chest pain as an indicator of coronary disease during exercise testing.

To determine the significance of anginal chest pain during exercise testing, a series of 302 patients undergoing coronary arteriography with exercise testing was reviewed. Of the 302 patients, 85 had ischemic ECG changes and chest pain (Group I); 87 patients had ischemic ECG changes but no chest pain (Group II); 25 patients had chest pain but no ischemic ECG changes (Group III); 105 patients had neither chest pain nor ischemic ECG changes (Group IV). Coronary artery disease was present in 95% of Group I, 75% of Group II, 72% of Group III, and 28% of Group IV. Of those patients with coronary disease, multiple vessels were involved in 94% of Group I, 51% of Group II, 67% of Group III, and 21% of Group IV. The predictive value for presence and extent of coronary disease showed Group I greater than Groups II and III greater than Group IV (p less than 0.025). We conclude that (1) anginal chest pain during exercise testing predicts the presence and extent of coronary disease more accurately than its absence; (2) the presence of chest pain even without an ischemic ECG response during exercise testing appears to be as predictive of coronary disease as an ischemic ECG response alone; and (3) the combination of anginal chest pain during exercise testing and an ischemic ECG response is highly predictive of multivessel coronary artery disease.

Angina Pectoris

ST segment changes post-infarction: predictive value for multivessel coronary disease and left ventricular aneurysm.

To ascertain whether exercise testing might predict multivessel coronary disease and left ventricular aneurysm after a myocardial infarction, 154 patients with a single documented myocardial infarction who had both exercise testing and coronary angiography were grouped according to whether they had greater than or equal to 1 mm ST depression, greater than or equal to 1 mm ST elevation, or neither during exercise testing: 83 patients developed ST depression alone (group 1); 22 patients had ST elevation with concomitant ST depression in other leads (group 2); 19 patients had ST elevation alone (group 3); and 30 patients had no ST changes (group 4). Multivessel disease, defined as greater than or equal to 70% luminal narrowing in two or more coronary vessels, was present in 76% (63 of 83) of group 1, 91% (20 of 22) of group 2, 21% (four of 19) of group 3, and 13% (four of 30) of group 4. A left ventricular aneurysm was present in 31% (26 of 83) of group 1, 68% (15 of 22) of group 2, 79% (15 of 19) of group 3, and 40% (12 to 30) of group 1. We conclude that ST changes during exercise testing in patients after a myocardial infarction can reliably predict the extent of coronary disease and the presence of a left ventricular aneurysm; ST depression with or without ST elevation predicts multivessel disease; ST elevation alone or a negative exercise test suggests single vessel involvement; and ST elevation with or without ST depression predicts left ventricular aneurysm.

Adult

ST-segment elevation during recovery from exercise. A new manifestation of Prinzmetal's variant angina.

Four patients underwent exercise testing because of a history of pain in the chest; all four developed marked elevation of the S-T segment only during recovery after exercise. Three of the four patients showed ST-segment depression during exercise, but ST-segment elevation was absent until two or more minutes after cessation of exercise. ST-segment elevation after exercise was accompanied by hypotension in three patients and by ventricular arrhythmias in one. Subsequent coronary angiographic studies revealed normal or minimally diseased coronary arteries in two patients and significant coronary lesions in the other two. Review of the literature shows that contrary to the prevailing belief, over half of the patients with Prinzmetal's variant angina have electrocardiographic changes diagnostic of ischemia during exercise testing. Over half of the patients with abnormal findings on tests during exercise display ST-segment elevation as a manifestation of ischemia; however, delayed ST-segment elevation of the type seen in these four patients is distinctly uncommon, having previously been described in only three individual case reports. The pathophysiology of this response is uncertain but may relate to rapid alterations in the autonomic balance during recovery after exercise.

Adult