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Journal of the American College of Cardiology | 1992

Lesion morphology and coronary angioplasty: Current experience and analysis

Richard K. Myler; Richard E. Shaw; Simon H. Stertzer; Harvey S. Hecht; Colman Ryan; Joseph Rosenblum; David C. Cumberland; Mary C. Murphy; Hansell Hn; Benito Hidalgo

From July 1, 1990 to February 28, 1991, 533 consecutive patients with 764 target vessels and 1,000 lesions underwent coronary angioplasty. Procedural success was achieved in 92.3%, untoward (major cardiac) events occurred in 3% (0.8% myocardial infarction, 1.3% emergency coronary bypass grafting and 0.9% both; there were no deaths). An unsuccessful uncomplicated outcome occurred in 4.7%. Lesion analysis using a modified American College of Cardiology/American Heart Association classification system showed that 8% were type A, 47.5% were type B and 44.5% were type C (36% of type B and 11% of type C were occlusions). Angioplasty success was achieved in 99% of type A, 92% of type B and 90% of type C lesions (A vs. B, p less than 0.05; B vs. C, p = NS; A vs. C, p less than 0.01). Untoward events occurred in 1.2% of type A, 1.9% of type B and 2% of type C lesions (p = NS). An unsuccessful uncomplicated outcome occurred in 0% of type A, 6% of type B and 7% of type C lesions (A vs. B, p less than 0.05; B vs. C, p = NS; A vs. C, p less than 0.05). Among the unsuccessful uncomplicated outcome group, occlusion occurred in 49%: 38% of type B and 59% of type C lesions. With B1 and B2 subtypes, success was obtained in 95% and 89.5% and untoward events occurred in 1.5% and 2.3% and an unsuccessful uncomplicated outcome in 3.7% and 8%, respectively. C1 and C2 subtyping showed success in 91% and 86%, untoward events in 1.3% and 6% and an unsuccessful uncomplicated outcome in 7.5% and 8.5%, respectively. Among the 764 vessels, success was obtained in 89.5% and untoward events occurred in 2.5% and an unsuccessful uncomplicated outcome in 8%. Assessment of lesion-vessel combinations showed a less favorable outcome with type C lesions and combinations of A-B, B-C and multiple (more than three lesions) type B and C vessels. Statistical analysis of morphologic factors associated with angioplasty success included absence of (old) occlusion (p less than 0.0001) and unprotected bifurcation lesion (p less than 0.001), decreasing lesion length (p less than 0.003) and no thrombus (p less than 0.03). The only significant factor associated with untoward events was the presence of thrombus (p less than 0.003). Predictors of an unsuccessful uncomplicated outcome included old occlusion (p less than 0.0001) and increasing lesion length (greater than 20 mm) (p less than 0.001), unprotected bifurcation lesion (p less than 0.05) and thrombus (p less than 0.03).


Journal of the American College of Cardiology | 1991

Silent ischemia after coronary angioplasty: Evaluation of restenosis and extent of ischemia in asymptomatic patients by tomographic thallium-201 exercise imaging and comparison with symptomatic patients

Harvey S. Hecht; Richard E. Shaw; Henry L. Chin; Colman Ryan; Simon H. Stertzer; Richard K. Myler

One hundred sixteen patients were evaluated to determine the ability of single photon emission computed tomographic (SPECT) thallium-201 exercise and redistribution imaging to detect silent ischemia secondary to restenosis in asymptomatic patients after single and multiple vessel percutaneous transluminal coronary angioplasty and the findings were compared with SPECT imaging detection of restenosis in symptomatic patients. The value of exercise electrocardiography (ECG) and the amount of ischemic myocardium in symptomatic and asymptomatic patients were determined. Forty-one patients were asymptomatic after angioplasty; 77% of these had chest pain before angioplasty. Seventy-five patients had chest pain after angioplasty; 99% of these had chest pain before angioplasty. Restenosis occurred in 61% of asymptomatic and 59% of symptomatic patients and in 46% of the vessels in both asymptomatic and symptomatic patients. Sensitivity, specificity and accuracy for detection of restenosis by SPECT in individual patients were 96%, 75% and 88% versus 91%, 77% and 85%, respectively, in the asymptomatic versus symptomatic groups (p = NS). Sensitivity, specificity and accuracy for restenosis detection in individual vessels were 90%, 89% and 89% versus 84%, 77% and 84%, respectively, in the asymptomatic and symptomatic groups (p = NS), with similar results for the three major arteries. Sensitivity and accuracy of exercise ECG were significantly less than those of SPECT imaging for the patients with silent (40% and 44%) and symptomatic (59% and 64%) ischemia (p less than 0.001). Restenosis of vessels in the patients with silent and symptomatic ischemia was associated with an equal amount and degree of severity of ischemic myocardium in the two groups.(ABSTRACT TRUNCATED AT 250 WORDS)


Journal of the American College of Cardiology | 1993

Coronary rotational ablation: initial experience in 302 procedures.

Simon H. Stertzer; Joseph Rosenblum; Richard E. Shaw; Irawan Sugeng; Benito Hidalgo; Colman Ryan; Hansell Hn; Mary C. Murphy; Richard K. Myler

OBJECTIVES The aim of this study was to assess the utility of percutaneous transluminal coronary rotational ablation in the treatment of coronary artery disease. BACKGROUND Although numerous advances have been made in the treatment of coronary artery disease, there are lesions with complex morphology that are not amenable to current intravascular therapy. METHODS A consecutive series of 242 patients having 302 coronary rotational ablation procedures was analyzed. One hundred nineteen (49%) of the patients had previously undergone attempted coronary angioplasty, which was unsuccessful in 31 patients (13%). The left ventricular ejection fraction was normal in 196 patients (81%). The ablation procedure was attempted in 308 vessels and 346 lesions. Of the 346 lesions treated, 26 (7.5%) were classified as American College of Cardiology/American Heart Association type A, and 320 (92.5%) as either type B or type C. RESULTS Procedural success was achieved in 284 (94%) of the 302 procedures and 330 (95.4%) of the 346 lesions in which ablation was attempted. Five procedures (1.7%) were unsuccessful, but no cardiac event occurred during the hospital stay. A major cardiac event occurred in 13 cases (4.3%); 9 (3%) of these complications were due to the ablation procedure. Six patients sustained a Q wave myocardial infarction alone, two had a Q wave infarction and required emergency surgery and one needed emergency surgery but did not have a Q wave infarction. No procedural deaths were attributed to the ablation procedure. Follow-up has been obtained in 182 of the 242 patients at a mean interval of 9 +/- 5 months. Of the 182 patients, 174 (95.6%) were alive and free of myocardial infarction. Angiographic follow-up is available thus far in 87 patients. By combining angiographic and clinical outcome, an overall estimated restenosis rate of 37.4% (68 of 182) was calculated. CONCLUSIONS These data suggest that coronary rotational ablation can be performed on lesions with a variety of morphologic features with high initial success rates. The overall rate of restenosis is similar to that of balloon angioplasty.


American Journal of Cardiology | 1990

Usefulness of tomographic thallium-201 imaging for detection of restenosis after percutaneous transluminal coronary angioplasty

Harvey S. Hecht; Richard E. Shaw; Thomas R. Bruce; Colman Ryan; Simon H. Stertzer; Richard K. Myler

The role of tomographic thallium-201 exercise and redistribution imaging in the detection of restenosis after percutaneous transluminal coronary angioplasty (PTCA) was evaluated in 116 patients: 61 (53%) with 1- and 55 (47%) with multivessel PTCA, with a total of 185 dilated vessels. Complete revascularization was performed in 89 (77%) and partial revascularization in 27 (23%) of the patients. Restenosis was angiographically demonstrated in 69 (60%) of the patients and 85 (46%) of the vessels 6.4 +/- 3.1 months after PTCA. Disease progression in previously normal vessels was noted in 11 patients. The results were: (1) for detection of restenosis in the group of patients, single-photon emission computed tomographic (SPECT) versus exercise electrocardiographic sensitivity was 93 vs 52% (p less than 0.001), specificity 77 vs 64%, and accuracy 86 vs 57% (p less than 0.001). The results were similar in the complete and partial revascularization groups. (2) SPECT was 86% sensitive, specific and accurate for restenosis detection in specific vessels with comparable results for 1-versus multivessel PTCA and complete versus partial revascularization. Sensitivity, specificity and accuracy were: 89, 95 and 92% for the left anterior descending coronary artery; 88, 79 and 82% for the right coronary artery; and 76, 83 and 85% for the left circumflex coronary artery. Eighty-one percent of the diseased nondilated vessels were correctly identified. (3) Disease progression to greater than 50% stenosis was detected with 91% sensitivity, 84% specificity and 85% accuracy. SPECT thallium-201 imaging is an excellent tool for the detection of restenosis and disease progression after PTCA in the settings of 1- and multivessel angioplasty and complete and partial revascularization.


American Journal of Cardiology | 1976

Impaired parasympathetic responses in patients after myocardial infarction

Colman Ryan; Milton Hollenberg; David B. Harvey; Robert Gwynn

To assess whether vagal and sympathetic responses are impaired 3 months after myocardial infarction, 27 patients, 15 age-matched control subjects and 13 young normal subjects underwent physiologic stress tests. In patients, facial immersion in water at 25 degrees and 0 degrees C provoked less slowing of heart rate than in age-matched control subjects. Young normal persons responded with the greatest reduction in heart rate. Response to facial immersion decreased linearly with age in normal subjects (Y = -0.97X+86). Isometric handgrip or cold pressor test elicited brisk increases in blood pressure in almost all patients, but the vagal response to facial immersion correlated poorly with such pressor responses. Thus, in the patients studied 3 months after myocardial infarction, the parasympathetic response to facial immersion was significantly impaired whereas sympathetic pressor responses remained intact.


Journal of The American Society of Echocardiography | 1993

Supine Bicycle Stress Echocardiography Versus Tomographic Thallium-201 Exercise Imaging for the Detection of Coronary Artery Disease

Harvey S. Hecht; Larry DeBord; Richard E. Shaw; Henry Chin; Robert Dunlap; Colman Ryan; Richard K. Myler

To compare the accuracy of supine bicycle stress echocardiography (SBSE), a new technique for evaluating coronary disease during peak exercise, with tomographic thallium-201 exercise imaging (SPECT), 71 patients were evaluated by SBSE, SPECT, and coronary arteriography. Twenty patients had normal coronary vessels; 22 had single-vessel, 14 had double-vessel, and 15 had triple-vessel disease. There were no differences in sensitivity (90% vs 92%), specificity (80% vs 65%), and accuracy (87% vs 85%) between SBSE and SPECT for the group of 71 patients. The results were similar in patients with and without prior myocardial infarction and with single-, double-, or triple-vessel disease. There were no differences between SBSE and SPECT for disease detection for the group of 213 individual vessels in sensitivity (88% vs 80%), specificity (87% vs 84%), and accuracy (88% vs 82%), but SBSE was more sensitive for the left anterior descending artery (97% vs 82%, p < 0.005) and for arteries involved in triple-vessel disease (93% vs 69%, p < 0.01) and more specific for the right coronary artery (88% vs 66%, p < 0.01). Supine bicycle exercise was associated with significantly lower maximal heart rates than treadmill exercise but with significantly higher systolic and diastolic blood pressures. There were no differences in heart rate x systolic blood pressure. We conclude that SBSE and SPECT are equally reliable for coronary disease detection in patients and for evaluation of disease in specific arteries with the exception of SBSEs higher sensitivity for the left anterior descending artery and arteries involved in triple-vessel disease and higher specificity for the right coronary artery.


Journal of The American Society of Echocardiography | 1993

Supine bicycle stress echocardiography: peak exercise imaging is superior to postexercise imaging.

Harvey S. Hecht; Larry DeBord; Nancy Sotomayor; Richard E. Shaw; Robert Dunlap; Colman Ryan

The abilities of peak exercise (PEAK) stress echocardiography versus postexercise (POST) stress echocardiography to detect coronary artery disease were evaluated in 136 consecutive patients undergoing supine bicycle stress echocardiography and coronary arteriography: 42 (31%) had normal coronary vessels, 38 (28%) had single-vessel disease, 34 (25%) had double-vessel disease, and 22 (16%) had triple-vessel disease. The results were as follows: (1) For detection of disease in the group of patients, sensitivity of PEAK versus POST was 94% versus 83% (p < 0.01) and specificity was 88% versus 90%. (2) For detection of disease in specific vessels, sensitivity of PEAK versus POST was 90% versus 72% (p < 0.0001) and specificity was 89% versus 92%. (3) For evaluation of the three major coronary arteries, sensitivity of PEAK versus POST was 96% versus 85% (p < 0.05) for the left anterior descending artery, 90% versus 65% (p < 0.01) for the right coronary artery, and 79% versus 60% (p < 0.05) for the left circumflex coronary artery. There were no differences in specificity. (4) The percent diameter stenosis of vessels normalizing from PEAK to POST versus vessels abnormal at PEAK and POST was 80.6% +/- 16% versus 85.9% +/- 14%, p = 0.07. There were no differences in exercise parameters between patients with and without resolution from PEAK to POST. (5) PEAK versus POST accuracy for identification of patients with multivessel disease was 93% versus 68% (p < 0.001). We conclude that stress echocardiography performed during peak exercise is superior to postexercise stress echocardiography.


American Journal of Cardiology | 1993

Usefulness of supine bicycle stress echocardiography for detection of restenosis after percutaneous transluminal coronary angioplasty

Harvey S. Hecht; Larry DeBord; Richard E. Shaw; Robert Dunlap; Colman Ryan; Simon H. Stertzer; Richard K. Myler

The role of supine bicycle stress echocardiography (SBSE) for detecting restenosis after percutaneous transluminal coronary angioplasty (PTCA) was evaluated in 80 patients: 41 (51%) with single and 39 (49%) with multivessel PTCA (total 129 dilated vessels). Total revascularization was performed in 54 (68%) and partial revascularization in 26 (32%) patients. Restenosis was angiographically demonstrated in 60 patients (75%) and in 72 vessels (56%) 6.1 +/- 2.9 months after PTCA. The results for detecting restenosis were: (1) SBSE versus exercise electrocardiographic sensitivity, 87 versus 55% (p < 0.001); (2) specificity, 95 versus 79%; and (3) accuracy, 89 versus 61% (p < 0.001). SBSE was 83% sensitive, 95% specific and 88% accurate for restenosis detection in specific vessels with comparable results for single versus multivessel PTCA and total versus partial revascularization. Sensitivity, specificity and accuracy were: 91, 93 and 91% for the left anterior descending coronary artery; 77, 94 and 85% for the right coronary artery; and 76, 96 and 88% for the left circumflex coronary artery. Ninety-four percent of the nondilated diseased vessels were correctly identified. It is concluded that SBSE is an excellent tool for identifying restenosis after PTCA.


Angiology | 1988

Sinus Node Suppression in Acute Strokes—Case Reports

Tali T. Bashour; Michael S. Cohen; Colman Ryan; Charles Antonini

The authors report on 5 patients, 4 of them observed over a period of only two months in one community hospital, who developed profound sinus node suppression in the early phase following acute strokes. This complication re sulted in the death of 2; in the remaining 3, it was controlled by electrical car diac pacing or intravenous atropine. In 3 patients, the strokes were due to subarachnoid hemorrhage, and in 2, they were secondary to vascular occlusion. In at least 4 patients, the prognosis seemed favorable from a neurologic stand point. Vagally mediated sinus node arrest may, therefore, represent a poten tially fatal complication of strokes and may be more frequent than currently appreciated. Continuous monitoring in the early phase of acute strokes and pacemaker therapy may be lifesaving in some patients. This and the general phenomenon of functional failure of the sinus node due to a variety of causes are discussed.


Journal of the American College of Cardiology | 1995

731-6 Longterm Followup and Crossover 15 Years After Coronary Angioplasty: Comparison of Angioplasty and Bypass Surgery Strategies

Richard K. Myler; Richard E. Shaw; Mary C. Murphy; Zipkin R; Robert Dunlap; Colman Ryan

To characterize the longterm outcome in patients who had successful coronary angioplasty (PTCA) and those who had an unsuccessful, uncomplicated procedure followed by elective bypass surgery (BYPASS) between 3/78 and 6/81, late followup was obtained in 196 (140 PTCA and 56 BYPASS) patients. Mean time to followup was 12 years (range = 13–16). There was no difference between the groups in survival (PTCA – 84.8%; BYPASS – 88.9%), late myocardial infarction (PTCA – 11.3%; BYPASS – 13.0%) or freedom from angina at latest contact (PTCA – 84.1 %; BYPASS – 87.0%). In the PTCA group, 110 (78.6%) were definitively treated with one or more PTCA procedures. In the BYPASS group, 46 (82.1%) were definitively treated with one or more bypass surgeries. Twenty (14.3%) of the PTCA group crossed over to BYPASS and 8 (14.3%) of the BYPASS group crossed over to PTCA. In conclusion, PTCA and BYPASS strategies yield comparable longterm results. Crossover rates between the two therapeutic procedures are similar. It appears that repeat procedures and crossovers are important in sustaining the beneficial results for both procedures over very long periods of time.

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Richard E. Shaw

California Pacific Medical Center

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Harvey S. Hecht

Icahn School of Medicine at Mount Sinai

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