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Biomedical subjects

A G Adelman

Publications and source records attributed to A G Adelman.

At least 37 records · Page 2Linked to original sources
PubMed1992

Acute coronary thrombotic occlusion following exercise testing 6 weeks after percutaneous transluminal coronary angioplasty.

Exercise stress testing is often performed following percutaneous transluminal coronary angioplasty (PTCA) in order to evaluate the efficacy of the procedure. Together with thallium-201 (Tl-201) scintigraphy, these noninvasive tests provide valuable data for predicting the recurrence of angina and restenosis. However, concerns regarding the safe timing of exercise testing post-PTCA have been raised in 3 previous case reports. Each case documents acute coronary occlusion shortly after stress testing performed within several days of successful angioplasty, leading to the recommendation that such testing be deferred up to 4 weeks following PTCA. This paper reports a patient in whom acute thrombotic occlusion of the left anterior descending coronary artery (LAD) occurred immediately after a mildly abnormal exercise Tl-201 stress test done 6 weeks after PTCA.

Adult↗
PubMed1992

Comparison of acute elastic recoil after directional coronary atherectomy versus standard balloon angioplasty.

We evaluated intraprocedural "elastic recoil" in 25 patients (22 men and 3 women) undergoing directional coronary atherectomy (DCA) of left anterior descending stenoses, and compared these with 25 temporally-matched (14 men and 11 women) patients having balloon angioplasties (PTCA). Quantitative arteriography was performed using the Coronary Measurement System (Leiden, The Netherlands), with "elastic recoil" defined as the difference in maximum device or balloon size minus residual minimum diameter. In addition, we determined the effects of relative device size, specific anatomic location (proximal/mid artery), lesion length, eccentricity (symmetry index), and dystrophic calcification on acute "recoil" severity after both procedures. Although initial coronary stenoses were similar (minimum stenotic diameter, DCA = 0.59 +/- 0.20 mm versus PTCA = 0.55 +/- 0.23 mm, p = NS), less "elastic recoil" was observed after atherectomy (DCA = 0.83 +/- 0.57 mm versus PTCA = 1.26 +/- 0.56 mm, p < 0.01), and this was confirmed by absolute recoil/maximum device size ratios (DCA = 23.5 +/- 16.0% versus PTCA = 41.6 +/- 13.8%, p < 0.01). Acute "elastic recoil" was also influenced by maximum device size/"normal" coronary artery ratios [(ratio < 0.9, DCA = 0.26 +/- 0.10 mm versus PTCA = 0.84 +/- 0.13 mm, p < 0.01); (ratio 0.9 to 1.1, DCA = 0.69 +/- 0.41 mm versus PTCA 0.75 +/- 0.32 mm, p = NS); (ratio > 1.1, DCA = 1.09 +/- 0.64 mm versus PTCA = 1.59 +/- 0.48 mm, p < 0.05)].(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1992

Acute outcome of directional coronary atherectomy vs standard balloon angioplasty in de novo left anterior descending stenoses.

To assess the immediate outcome of directional coronary atherectomy (DCA) versus standard balloon angioplasty (PTCA) in de novo left anterior descending coronary stenoses, 25 consecutive atherectomies (22 men, 3 women) performed at The Toronto Hospital, between July 1990 and March 1991 were compared with 25 (14 men, 11 women) temporally matched successful angioplasties. Coronary stenoses were analyzed by quantitative arteriography, using the Coronary Measurement System (Leiden, The Netherlands), with estimation of transstenotic hemodynamics by fluid dynamic equations. Before and after procedure qualitative blood flow (TIMI criteria) was also evaluated, as was intimal haziness and coronary dissection. In comparison to PTCA, coronary atherectomy produced less residual minimum stenotic diameter (DCA, 2.75 +/- 0.55 vs PTCA, 1.70 +/- 0.44 mm, p < 0.001), and relative percent diameter stenosis (DCA, 17.9 +/- 10.7 vs PTCA, 34.4 +/- 10.7 percent, p < 0.001), with less transstenotic obstructive gradient (DCA, 0.2 +/- 0.2 vs PTCA, 1.0 +/- 1.5 mm Hg, p < 0.05), and greater estimated stenotic flow reserve (DCA, 4.86 +/- 0.15 vs PTCA, 4.50 +/- 0.48 x baseline, p < 0.05). Coronary atherectomy "normalized" TIMI flow patterns in virtually all patients (DCA, 2.96 +/- 0.20 vs PTCA, 2.72 +/- 0.45, p < 0.05), while creating less intimal haziness (DCA, 10/25 [40 percent] vs PTCA, 23/25 [92 percent], p < 0.01), and coronary dissection (DCA, 6/25 [24 percent] vs PTCA, 16/25 [64 percent], p < 0.05). Therefore, when compared with standard balloon angioplasty, DCA produces less residual stenosis, better transstenotic hemodynamics, while decreasing the frequency of coronary artery damage, in de novo left anterior descending stenoses.

Adult↗
PubMed1992

Directional coronary atherectomy at the Toronto and Mount Sinai Hospitals: report of the initial 120 procedures.

OBJECTIVE: To assess the procedural success and complication rates of the first 120 directional coronary atherectomy cases performed at two Toronto hospitals. DESIGN AND SETTING: Case series in tertiary referral centres. PATIENTS: One hundred and thirteen patients in whom 120 atherectomy procedures were attempted between July 1990 and April 1992. INTERVENTION: Directional coronary atherectomy. MAIN RESULTS: Angiographic success was obtained in 115 of 120 procedures (96%) involving 117 of 123 lesions (95%). Procedural success (angiographic success without death, myocardial infarction or coronary bypass surgery) was obtained in 110 of 120 procedures (92%). Adjunctive balloon angioplasty was required in 20 procedures (17%). There was one death at 36 h in an elderly patient who underwent an emergency procedure while in cardiogenic shock. Periprocedural non-Q wave myocardial infarction occurred in five patients. There were no Q wave myocardial infarctions. Three patients required coronary bypass surgery prior to discharge and vascular complications occurred in five patients. CONCLUSIONS: Directional coronary atherectomy can be performed with procedural success and complication rates comparable to conventional balloon angioplasty. Randomized trials are underway to determine if atherectomy results in a lower restenosis rate.

Adult↗
PubMed1990

Twelve-lead electrocardiogram recording during percutaneous transluminal coronary angioplasty. Analysis of reciprocal changes.

Coronary angioplasty was used as a human model of transient myocardial ischemia to evaluate the electrocardiographic characteristics and significance of "reciprocal" ST-segment depression and T wave changes. Continuous 12-lead ECGs were recorded before and during coronary angioplasty in 20 patients, 19 of whom had single vessel disease. In 12 of 14 patients, LAD occlusion produced ischemic changes (peaked T and/or ST elevation) in L1, AVL and at least two precordial leads. "Reciprocal" changes (ST depression and/or T inversion) were observed in at least two inferior wall leads. One patient had ST depression in V4-V6 with no change in the inferior leads and in the other the only ECG change was inferior ST depression with partial inversion of the T wave. In four of six patients, RCA occlusion produced ischemic changes in at least two inferior wall leads and "reciprocal" changes in L1, AVL and at least two anterior wall leads. In LAD as well as RCA occlusions "reciprocal" changes were characterized by inversion of the T wave or inversion of its ascending limb with or without ST depression. The magnitude of the ischemic changes tended to be proportional to the magnitude of the "reciprocal" changes. Our data suggest that: (1) "Reciprocal" changes are not a specific indicator of distant myocardial ischemia due to multivessel disease; (2) the magnitude of ischemic changes correlates with the magnitude of "reciprocal" changes; (3) "Reciprocal" changes may be the only manifestation of acute myocardial ischemia; and (4) "Reciprocal" changes may be represented by inversion of the T wave without displacement of the ST-segment.

Angioplasty, Balloon, Coronary↗
PubMed1983

Effect of negative pleural pressure on left ventricular hemodynamics.

Negative pleural pressure alters left ventricular (LV) function. LV volume changes have been studied in human subjects, but little is known of the hemodynamic effects. The effect of changes of pleural pressure on LV hemodynamics during a Mueller maneuver (inspiration against an obstruction) was studied in 11 subjects and during quiet, unobstructed inspiration in 3. During the Mueller maneuver, there was an initial decrease in pulmonary wedge pressure and aortic systolic pressure, almost as great as the decrease in pleural pressure. Thereafter, these pressures increased despite a sustained reduction in pleural pressure. Toward the end of the Mueller maneuver, pulmonary wedge transmural pressure averaged 31 +/- 12 mm Hg and in 6 patients large v waves developed. The increase in aortic transmural pressure averaged 30 +/- 16 mm Hg. Aortic pulse pressure decreased on the first beat from control levels of 59 +/- 21 to 47 +/- 21 (p less than 0.001) and then returned to control levels. During normal breathing in 3 subjects, studied with intraesophageal balloons, there was a similar increase in both transmural aortic and transmural pulmonary wedge pressures with a decrease in pleural pressure 6 mm Hg during inspiration. Thus, increased negative pleural pressure was associated with a marked increase in pulmonary wedge transmural pressure; the increase was approximately proportionate to the decrease in pleural pressure. It is suggested that this increase was due to increased impedance to LV ejection and to right ventricular expansion interfering with LV diastolic filling.

Adult↗
PubMed1983

Initial experience with universal pacemakers.

Thirty-five patients were implanted with the Sequicor DDD pacemaker between September 1, 1981 and March 1, 1982. The mean age was 61.7 years (range, 17-88). According to their ECGs, the patients fell into two distinct groups--those with A-V block and those with sick sinus syndrome. Our initial experience has indicated an excellent electronic component function (except for 1 discrepant reed switch); high battery drain of the Sequicor; complications similar to those seen with DVI or VVI pacing; and an increase in the hemodynamic benefits resulting from DDD as compared to DVI or VVI pacing in 70% of patients.

Adolescent↗
PubMed1981

Prinzmetal's angina with documented coronary artery spasm. Treatment and follow-up.

Eighteen patients with Prinzmetal's angina were studied angiographically and 17 were followed for an average of 27 months. The were 12 men and six women, with a mean age of 46.3 years. The mean duration of symptoms before clinical diagnosis was 4.1 weeks. Four had had a previous myocardial infarction. Six patients had spontaneous cardiac arrests within 48 hours of diagnosis and hospital admission. At coronary arteriography, 10 patients had significant coronary artery disease; two of these had coronary artery spasm. The remaining eight patients had normal cornary arteries with significant coronary artery spasm at arteriography. Angiographic mitral valve prolapse was found in eight patients; seven of these had inferior ST segment elevation with pain. Six of the 10 patients with significant coronary artery disease had aortocoronary bypasses performed with good results. Ten of the remaining 11 patients who were treated medically had their symptoms controlled with oral isosorbide dinitrate alone or in combination with propranolol, nifedipine or perhexiline but propranolol may have an adverse effect. Though the initial clinical course in untreated patients was unfavourable, progress after starting treatment was good, with no further cardiac arrests, myocardial infarctions, or deaths.

Angina Pectoris↗
PubMed1981

Experience with ergonovine provocative testing for coronary arterial spasm.

We reviewed our experience with the ergonovine provocative test for coronary arterial spasm in 40 patients with pain in the chest believed to be angina pectoris and in one patient with a myocardial infarction and normal coronary arteries. Twenty-nine patients had normal coronary arteries, while 12 had mild to moderate lesions. Ergonovine maleate was administered incrementally in total cumulative doses of 0.25 mg to 1.2 mg. The effect of ergonovine on coronary arterial caliber was determined by comparing the arterial diameter from the angiogram obtained after administration of ergonovine with that from the control. Measurements were made at the same preselected points in both films and also at points of greatest response. Excluding the three cases with complete occlusion, the mean reduction in coronary arterial diameter at preselected points was 12 +/- 15 percent. When the points of greatest response were examined, the maximum reduction in coronary arterial diameter was less than 25 percent in 13 patients, 25 to 50 percent in 20 patients, and more than 50 percent in eight patients. The patterns of response included complete occlusion of a vessel in the three patients with variant angina, diffuse narrowing in 16, diffuse and focal narrowing in six, and spasm at the catheter tip in three patients. All patients with maximum reductions of more than 50 percent in coronary arterial diameter and six of those with maximum reductions of 25 to 50 percent had pain in the chest, but only the three with complete occlusion had associated changes in the S-T segment. Thus, the response in patients with variant angina represents one end of a spectrum of responses to administration of ergonovine. In addition, a large number of patients may have ergonovine-induced pain in the chest without electrocardiographic changes and only an intermediate degree of coronary arterial spasm.

Adult↗
PubMed1980

Aortocoronary bypass in patients with severe left ventricular dysfunction.

The results of aortocoronary bypass grafting in 29 patients with severe left ventricular dysfunction (ejection fraction less than 35%) were studied. All patients had severe angina pectoris; 17 patients has class IV heart function and 12 had class III function according to the New York Heart Association classification. Intra-aortic balloon pump support was instituted preoperatively in all patients. Three patients died in the perioperative period. Survivors were followed up for a mean period of 20 months; there were three late deaths. Sixteen patients were clinically improved; 8 had class I and 8 class II heart function at follow-up. Fourteen patients underwent cardiac catheterization postoperatively at a mean time of 19 months. Although 22 (79%) of the 28 grafts were patent, there was no significant improvement in resting left ventricular dysfunction as assessed by ejection fraction, left ventricular volume or left ventricular end-diastolic pressure. Furthermore, graft patency could not be correlated with improvement in segmental wall motion. There was a 10% operative and an 11.5% late mortality and no measurable improvement in resting left ventricular function in this study but the majority (73%) of the surviving patients experienced definite clinical improvement.

Angina Pectoris↗
PubMed1976

Prinzmetal's angina with coronary artery spasm. Angiographic, pharmacologic, metabolic and radionuclide perfusion studies.

We studied the effects of coronary artery spasm on perfusion of the microvasculature in a patient with Prinzmetal's angina. Intracoronary injections of 99mTc and 131I-labelled macroaggregated human serum albumin were performed (1) at rest, (2) during spontaneous angina, (3) after the administration of nitroglycerin and (4) during pacing-induced spasm and the resultant scans compared. The resting scan was normal. Pain and spasm were associated with a perfusion defect that was localized to the anterior and inferior walls of the left ventricle. The localization of the perfusion defect corresponded with angiographically demonstrated spasm involving left anterior descending and distal circumflex coronary arteries. A subsequent myocardial infarction was localized by 43K scanning to the same perfusion area. Metabolic and parasympathetic stimulation studies were performed but were inconclusive. The patient's recurrent pains were ultimately controlled with large oral doses of isosorbide dinitrate.

Angina Pectoris↗
PubMed1976

Evolving indications for preoperative intraaortic balloon pump assistance.

Over a two-year period about 1,000 operations were performed with cardiopulmonary bypass. Intraaortic balloon pump assistance (IABP) was employed on 150 occasions, and a review of these has permitted clarification of the indications for its use. Sixty patients had IABP for carcinogenic shock either after infarction or cardiotomy, and 37 (62%) survived. Preoperative IABP in 90 high-risk patients resulted in survival for 79 (88%). The indications for prophylactic IABP included: (1) relief of severe pain, which occurred in 42 patients with acute coronary insufficiency, (2) improvement in the coronary perfusion pressure, which was accomplished in 20 patients with significant left main coronary artery occlusion or its equivalent, and (3) protection of left ventricular function, which war carried out in 28 patients with an LV ejection fraction of less than 0.40. The significance of the preoperative endocardial viability ratio (EVR) in relation to prophylactic IABP was also assessed: an EVR below 0.70 appears to be an indication for preoperative IABP.

Assisted Circulation↗
PubMed1976

Prognostic significance of endocardial viability ratio in aortocoronary bypass surgery.

Although aortocoronary bypass (ACB) for patients with stable angina carries a low mortality, some unexpected deaths do occur. Since in patients with normal coronary arteries the endocardial viability ratio (EVR) can be correlated with subendocardial perfusion, with a ratio of 0.7 or less indicating ischemia of the left ventricular subendocardium, and since the EVR postoperatively is useful in determining the need for intra-aortic balloon pump assist (IABPA), it was decided to ascertain whether the EVR might have prognostic value in patients with stable angina scheduled for standard ACB. Three groups of patients were studied: 50 with stable angina, 24 who had died after ACB, and 18 who required IABPA for cardiogenic shock after surgery for stable angina. No significant differences were found for cardiac index, left ventricular end-diastolic pressure, left ventricular ejection fraction and pre- and postoperative artery scores, but there were significant differences in the EVR between the first and second groups and between the first and third groups (P less than 0.01 in each instance). These findings suggest that the left ventricular EVR may indeed be of prognostic value in patients scheduled to undergo ACB and that use of IABPA, which produces an increase in EVR, may be useful in patients with EVRs of less than 0.7, even if other parameters of cardiac function are normal.

Angina Pectoris↗