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M S Gotsman

Publications and source records attributed to M S Gotsman.

At least 73 records · Page 4Linked to original sources
PubMed1995

Thrombolysis in the era of the randomized trials.

Thrombolytic therapy in acute myocardial infarction is of established value in recanalizing the occluded coronary artery, reducing infarct size, and decreasing mortality. Here, we review the extensive information provided by large clinical trials on agent and patient selection, timing of treatment, adjuvant therapies, and complications. Early treatment is of prime importance. Tissue plasminogen activator is slightly superior to streptokinase, especially in young patients treated early. Intravenous heparin should be used in conjunction with tissue plasminogen activator, although its role when streptokinase is used is less clear. Aspirin, beta-blockers, and converting enzyme inhibitors are of proven value as adjunctive therapies; nitrates and magnesium are not. Newer antithrombotic and antiplatelet agents (eg, hirudin and glycoprotein IIb/IIIa receptor antagonists) may further improve results.

Combined Modality Therapy↗
PubMed1995

Combined mechanical and thrombolytic treatment for totally occluded bypass grafts.

Totally occluded venous grafts are usually less amenable to mechanical reperfusion alone (for example percutaneous transluminal coronary angioplasty, PTCA) because of the large mass of thrombotic material within the graft. A combined approach using mechanical and thrombolytic treatment might therefore be more successful. Twenty one patients (20 males, one female) with a mean age of 64.5 (SD 5.6) years underwent angiography because of crescendo or unstable angina (n = 19) or myocardial infarction (n = 2) at a mean of 21.7 (18.6) days after onset of symptoms (range 1-60). All patients had had coronary artery bypass grafting (CABG) at a mean of 8.02 (4.02) years (range 0.3-13 years) before the current admission. At catheterisation, totally occluded venous bypass grafts to the left anterior descending coronary artery or diagonal (n = 10), marginal (n = 6), or right coronary artery (n = 5) were found. A combination of PTCA and thrombolytic treatment (in eight patients extended thrombolysis for 24 hours) was successful in reopening the venous graft in 16/21 patients (76.2%). Immediate complications included femoral haematoma (4), distal embolisation (3), and infection in one patient. Out of 13 patients catheterised within three months, two had reoccluded, seven had restenosis, while four had patent grafts. Recurrent PTCA (at least once more) was done in eight patients. At long term follow up of a mean of 26.7 (21.6) months (range 4-75 months), four patients were asymptomatic, eight still suffered from mild stable angina, while three had recurrent hospital admissions and needed a second coronary artery bypass. A combination of thrombolytic treatment and PTCA is a feasible and practised approach to recanalise recently occluded venous bypass grafts.

Aged↗
PubMed1995

[Angioplasty for vein grafts and native coronary arteries after previous coronary artery bypass grafting].

219 patients after previous coronary artery bypass grafting (CABG) underwent coronary artery or vein graft angioplasty in 1984-1991. 452 stenotic lesions out of 498 were successfully dilated in 337 procedures (90.7%). For arterial lesions the initial success rate had been 89.2% (321/360) and for vein graft lesions 94.9% (131/138). For repeated angioplasty the success rate was the same. Major complications included 3 deaths (0.9%). 15 myocardial infarctions (5.3%) and 1 emergency CABG. Factors that had reduced the success rate were lesions at the proximal anastomosis, total occlusions, and complex (type C) lesions. Time since grafting did not affect success rate of the second procedure. Restenosis after successful angioplasty was 37.3% (34/91) for arterial lesions and 56.8% (25/44) for graft lesions, after a mean time of 11.2 +/- 2.7 months. Restenosis was more common in type C lesions and old vein grafts. There was considerable improvement in treadmill exercise time of patients after the angioplasty (5.92 vs 7.31 minutes) and in double product. During a follow up of about 3 years, 7.6% (15/196) died of cardiac events, 5.2% (10/189) had myocardial infarctions, 10.5% (20/189) were reoperated and 31.0% (68/219) needed at least 1 repeat angioplasty. Long term followup was better after angioplasty of native arteries than of grafts. After angioplasty of vein grafts, there were more cardiac related deaths, more MIs and more reoperations than after angioplasty of native arteries: 11.5% vs 3.5%, 9.6% vs 2.8%, 21% vs 4.9%, respectively, than in the arterial group. Considering the high mortality and morbidity of reoperation, balloon angioplasty in selected patients may be the preferred strategy. Clinical and angiographic results are better after re-angioplasty of native arteries than vein grafts.

Angioplasty, Balloon, Coronary↗
PubMed1994

[The vascular stent in percutaneous coronary revascularization].

Balloon angioplasty is commonly used for coronary revascularization. Coronary stents were introduced to overcome its 2 main limitations: acute coronary occlusion and restenosis. We describe our experience with the use of 27 coronary stents in 26 patients. The indications for stenting were acute or threatened coronary occlusion in 16 patients, in 7 recurrent restenosis, and vein graft narrowing in the rest. Stent deployment was successful in all cases and there was no mortality. The hospital course was complicated by subacute thrombotic occlusion of the stent (2 patients) initially treated by balloon angioplasty, retroperitoneal bleeding (3), and surgical closure of femoral pseudoaneurysm (2); 22 were discharged without complications; 1 patient required coronary bypass. Coronary stenting has a high rate of success and is very effective in cases of abrupt coronary occlusion which would otherwise require emergency surgery. It is probably associated with a lower restenosis rate than standard balloon angioplasty. Accurately monitored anticoagulant therapy is essential to prevent complications.

Angioplasty, Balloon, Coronary↗
PubMed1994

Creation and healing of severe coronary dissection by the use of oversized balloon for the treatment of restenosis after an initially successful angioplasty.

We describe two patients who underwent successful coronary angioplasty with a balloon that matched the normal size of the artery. Both patients returned for a second angioplasty because of restenosis. The morphology of the restenotic lesion was very similar to that of the original lesion. In the second angioplasty a larger balloon was used, and in both cases severe dissection occurred. Repeat angiography 3 months later demonstrated an open artery with clinically insignificant residual stenosis. We believe that in these two cases the initial angioplasty stretched the artery and it recoiled slowly to its original dimensions. A larger balloon size was necessary to crack atherosclerotic plaque and cause a successful long-term outcome.

Aged↗
PubMed1994

Differentiation of periodic from nonperiodic low-frequency heart rate fluctuations.

Periodic low-frequency (LF) fluctuations of heart rate (HR) may be of diagnostic and prognostic value in diverse pathologic cardiopulmonary conditions. Two principal components of LF HR rate variations may be distinguished: periodic fluctuations and nonperiodic, nonstationary changes. The frequency content of these two components may overlap considerably. In order to avoid a tedious work-intensive visual analysis an efficient computer-based method for detection, differentiation, and quantitation of these signals is required. Two methods for separating periodic from nonperiodic HR changes are presented, namely, detrending and bandwidth (BW) calculation. A group of healthy individuals was evaluated in order to assess these methods in individuals with significant LF periodic episodes (15 patients) contrasted to those without LF periodic episodes (94 patients). The commonly used method of detrending consists of a fitted polynomial which by subtraction removes low frequencies originating from nonstationary changes without affecting periodic fluctuations. We found, however, that the frequencies involved in nonstationary and periodic fluctuations often overlap and thus the detrending method may not be highly efficient. In a second method we postulated different shapes for power spectrum curves of periodic and nonperiodic episodes. This latter method is based on BW calculation of the LF component of the R-R power spectrum and proved to be more efficient in detecting periodic episodes. It showed higher significance levels for the difference between the periodic and nonperiodic groups when the BW or the ratio between peak power and BW in the LF range was used. This new, alternative detection method may be employed in further studies which seek to elucidate the clinical relevance of the LF range and, in particular, the mechanisms for such long-wavelength periodic fluctuations.

Adolescent↗
PubMed1994

The effect of overdrive pacing rate and duration on ventricular escape rhythms in patients with chronic complete atrioventricular block.

The effect of overdrive (OD) pacing rate and duration on subsidiary pacemakers was evaluated in 54 patients with third-degree AV block. They had a permanent pacemaker implanted 61 +/- 56 months earlier because of complete AV block in 38 patients and, in 16 patients because of second-degree AV block, which in the interim advanced to complete AV block. The patients had a reliable infranodal escape rhythm, with a mean cycle length of 2,022 +/- 603 msec, upon discontinuation of the ventricular OD pacing, at a rate of 40 beats/min. The escape interval and escape rhythm cycle length was evaluated after OD pacing at 40, 50, 60, 70, 90, and 100 beats/min for 30 seconds, at each rate. In 100% of the patients the subsidiary pacemaker recovered after OD pacing at 40 and 50 beats/min and the number decreased to 59% at a rate of 100 beats/min. The escape interval prolonged gradually between OD pacing at 40 and 100 beats/min, by 56%. The effect of OD pacing duration at 50 and 70 beats/min was evaluated. At an OD pacing rate of 70 beats/min there was a significant effect of the pacing duration on the escape interval. There were significant differences in the escape interval duration and escape rhythm cycle length between males and females, patients with or without coronary artery disease, and patients with narrow or wide QRS escape. However, the increase in the OD pacing rate had a similar effect on the escape interval in the above mentioned groups. There was no effect on the paced QRS duration and sinus cycle length at each OD pacing rate.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1994

The earliest diagnosis of acute myocardial infarction.

Acute myocardial infarction results from the cessation of myocardial blood flow caused by thrombotic occlusion of a coronary artery. Rapid restoration of blood flow to the ischemic myocardium minimizes cardiac damage and improves early and long-term morbidity and mortality. Chest pain is the first symptom of myocardial infarction, but in some patients with silent ischemia, the disease can be diagnosed only in retrospect. In symptomatic patients, myocardial infarction should be accurately and promptly diagnosed so that reperfusion therapy can begin immediately. Electrocardiography is the simplest diagnostic modality. Although regional ST-segment elevation is specific, it is not sensitive. In contrast, new computerized algorithms for electrocardiographic analysis and serial monitoring increase sensitivity without decreasing specificity. In the emergency room, echocardiography is used to diagnose patients with no prior history of coronary artery disease whose electrocardiograms proved nondiagnostic. Time-consuming perfusion nuclear studies are inferior to echocardiography but may nevertheless enable physicians to diagnose myocardial infarction in the emergency room. Although the presence of excess creatine kinase is a sign of myocardial necrosis, its increase is delayed for a few hours after coronary occlusion. Doctors can diagnose myocardial infarction as early as two hours after coronary occlusion with the help of simpler automatic assays of MB-creatine kinase mass that use monoclonal antibodies. Other investigational markers of myocardial necrosis include myoglobin and troponin. Elevation of a circulating protein marker also signifies established necrosis, but physicians hope to achieve reperfusion through therapy before irreversible damage occurs.

Creatine Kinase↗
PubMed1994

Breast artifact in planar cardiac imaging: a comparison of 201T1 to sestamibi-99mTc.

Breast artifact occurrence during 201T1 myocardial image interpretation is a significant problem. We serially evaluated 3 female patients utilizing exercise treadmill perfusion studies in order to assess the potential role of 99mTc-Sestamibi (MIBI) imaging in the setting of documented 201T1 breast artifact. Both visual and quantitative analyses revealed no superiority of 99mTc-MIBI over 201T1 imaging in reference to avoidance of breast artifact. The variation in artifactual cardiac imaging defects in the 3 patients most probably reflected variations in breast positioning. Finally, the ability to assess ventricular wall motion via gated 99mTc-MIBI imaging may help to confirm an artifactual versus an actual myocardial perfusion abnormality.

Aged↗
PubMed1994

Total coronary artery occlusion late after successful coronary angioplasty of moderately severe lesions: incidence and clinical manifestations.

Coronary restenosis after balloon angioplasty is a slow process that develops over a few months. In some patients, with an initially successful angioplasty, an artery that originally had only moderate stenosis becomes totally occluded as a result of restenosis. This report describes 16 such patients out of 415 dilated lesions with late angiographic follow-up. Ten patients presented with stable angina pectoris, 5 had unstable angina and only one was admitted with a small myocardial infarction. Visible collaterals were present in 15 patients. Except for the patient who sustained myocardial infarction, none of the late angiograms showed the typical morphological features of acute lesion. We conclude that total coronary occlusion late after successful angioplasty of an artery that was moderately narrowed is rare. The 'restenotic' occlusion is a slow process that stimulates collateral formation and thus the risk of myocardial infarction is small.

Adult↗
PubMed1994

Silent myocardial ischemia during exercise testing: does it indicate a different angiographic and prognostic syndrome?

The prognostic significance of silent myocardial ischemia detected during graded exercise testing (GXT) is uncertain. The angiographic characteristics and long-term follow-up of 83 patients with silent ischemia (group 1), mean age 58 +/- 9 years, were compared with 83 age- and sex-matched patients with typical angina pectoris (group 2). Basic characteristics and mean follow-up (42 +/- 22 months) were similar in both groups. Patients with silent ischemia were characterized by longer duration of exercise test (6.5 vs. 4.8 min, p < 0.01), larger extent of maximum ST depression during peak exercise (2.4 vs. 2.0 mm, p < 0.01) and higher maximal double product at peak exercise (24,650 vs. 20,825, p < 0.01) compared to group 2. Long-term follow-up revealed similar rates of mortality (3.6 vs. 4.8%, p = NS) and major cardiac events (19.3 vs. 21.7%, p = NS). However, patients with typical angina tended to have more revascularization procedures (81 vs. 61%, p < 0.1). Thus, patients with silent ischemia have a better GXT capacity compared to patients with typical angina pectoris. Despite a similar severity of coronary involvement, patients with typical angina pectoris tend to have more revascularization procedures, yet the long-term prognosis appears similar.

Angina Pectoris↗
PubMed1994

Value of dobutamine/nitrate radionuclide angiography in predicting revascularization effects on ventricular function.

OBJECTIVE: Dobutamine and Nitrate Radionuclide Angiography (RNA) may help to distinguish viable from nonviable myocardium and to predict revascularization effects on LV function. SETTING: Ambulatory. EXPERIMENTAL DESIGN: Prospective. PATIENTS AND METHODS: We studied 12 patients (11 male, 1 female; mean age 56 +/- 10 years) with three-vessel disease, severe LV dysfunction, and prior MI for a mean follow-up time of 10 +/- 3.4 months. Thallium-201 scintigraphy favored potential viability in all patients: inducible ischemia with satisfactory perfusion in more than one coronary arterial territory. Global and regional LVEF's were calculated from preoperative RNA (baseline rest study and with continuous dobutamine infusion with gradual rate increase plus oral nitrates) and postoperative RNA at 1 and 6 months. RESULTS: There was no operative mortality, but two late deaths occurred. Symptomatically, most patients showed improvement. Global LVEF increased during dobutamine and nitrates preoperatively (p < 0.01), but not at 1 and 6 months postoperatively (without pharmacological intervention). Mean LVED volume was not significantly changed postoperatively. Regional EF improvement was found in 4 out of 9 LV wall segments under dobutamine and nitrates, and this increase persisted postoperatively at 1 and 6 months. CONCLUSIONS: Mild but significant increase in global LVEF during dobutamine and nitrates administration is not predictive of postoperative LVEF improvement. However, regional EF improvement appears to be predictive of post-revascularization LV functional improvement.

Administration, Sublingual↗
PubMed1994

Transient neurological events during dipyridamole stress test: an arterial steal phenomenon?

Dipyridamole-associated adverse neurological side effects have not been extensively described. We present two cases of dipyridamole-associated transient motor neurological events with no evidence of residual neurological deficits detected clinically or by head CT. The patients showed no evidence of significant extracranial (internal carotid) artery disease. We propose the presence of a regional cerebral perfusion disturbance due to an intracranial vascular steal phenomenon as the mechanism for the above side effects of dipyridamole.

Aged↗
PubMed1993

Clinical and angiographic predictors of immediate recoil after successful coronary angioplasty and relation to late restenosis.

The effect of immediate recoil on the results of balloon angioplasty was examined in a group of 416 patients (596 lesions) who underwent successful coronary angioplasty. Immediate recoil was responsible for loss of 0.42 +/- 0.64 mm from the potentially achievable lesion diameter, and represented 23% of the actual gain in diameter. The immediate recoil was determined mainly by the degree of arterial stretch, which is best represented by the balloon to normal artery size ratio (correlation coefficient 0.49, p < 0.0001). Classic risk factors for coronary artery disease did not affect immediate recoil, except for a trend toward lower values in patients with history of hypercholesterolemia. There was a tendency for lower recoil in patients with residual coronary thrombus and in those who underwent angioplasty within 1 week of acute myocardial infarction. Recoil was larger in the left anterior descending artery than in the circumflex or the right coronary artery. Patients with more immediate recoil developed more restenosis (> 50% stenosis at follow-up). However the late loss of luminal diameter due to the restenotic process was smaller in those who had larger initial recoil. It is concluded that immediate recoil after balloon angioplasty is an elastic phenomenon that is related mainly to the degree of arterial stretch. The relative importance of immediate recoil in determining the late outcome of coronary angioplasty is at least as important as the late restenotic process.

Angioplasty, Balloon, Coronary↗