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J Rosenblum

Publications and source records attributed to J Rosenblum.

At least 19 recordsLinked to original sources
PubMed1992

Lesion morphology and coronary angioplasty: current experience and analysis.

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).

Angioplasty, Balloon, Coronary↗
PubMed1992

Feasibility and safety of transesophageal stress echocardiography.

To determine the feasibility and safety of transesophageal stress echocardiography (TSE), 86 patients with chest pain syndrome were studied. The TSE test consists of transesophageal atrial pacing during simultaneous monitoring of left ventricular contractility by the use of transesophageal echocardiography. An octapolar pacing catheter attached to the transesophageal echoscope was used in conjunction with a cardiac stimulator to induce pacing-tachycardia. The optimal pair of electrodes was chosen from 13 possible combinations of the 8-electrode catheter. The pacing rate was increased until greater than or equal to 90% maximal age-predicted heart rate was reached or significant wall motion abnormalities were developed. The test was also stopped if ischemic electrocardiographic changes or progressive chest pain occurred. A successful TSE test was performed on 77 patients (90%). Twenty-one patients (24%) developed Wenckebach AV block during pacing that was resolved by intravenous atropine sulfate in all but one of them. The TSE test could not be completed in nine patients (10%) because we were unable to capture in four patients (5%), there were suboptimal images in three patients (3%), and two patients suffered intolerable epigastric discomfort (2%). Pacing-induced wall motion abnormalities were identified in 53 patients (69%). No serious complications were noted. We conclude that TSE is a feasible nonexercise stress test that can be performed safely in patients with suspected coronary artery disease.

Adult↗
PubMed1991

Brachial rotational atherectomy.

The brachial approach adds a new dimension to rotational atherectomy. The two cases presented included a large ectopic right coronary artery and a right internal mammary graft where both outcomes were successful. These cases demonstrate that the brachial approach can facilitate rotational atherectomy when greater guide support is necessary.

Aged↗
PubMed1991

Multiple coronary artery aneurysms in an adult associated with extensive thrombus formation resulting in acute myocardial infarction: successful treatment with intracoronary urokinase, intravenous heparin, and oral anticoagulation.

A 37-yr-old white female was admitted to hospital with an evolving anterior myocardial infarction. Coronary arteriography revealed multiple aneurysms in the left anterior descending (and right) coronary arteries. In the left anterior descending artery, there was evidence of extensive thrombus formation. The patient was successfully treated with intracoronary urokinase, intravenous heparin, and oral warfarin. There was partial thrombolysis in 16 hr and complete thrombolysis noted 6 wk later. This case of multiple coronary aneurysms, secondary to presumed Kawasaki disease, is the first documentation of antemortem intra-aneurysmal coronary thrombosis treated successfully by thrombolytic and anticoagulant therapy.

Administration, Oral↗
PubMed1991

Rotational ablation of chronic coronary occlusions.

Rotational ablation was performed successfully in three chronic coronary occlusions. At 3 months follow-up, two of the three lesions were patent. These cases illustrate the overall advantages and unique technical aspects of this device.

Adult↗
PubMed1991

Transesophageal stress echocardiography: detection of coronary artery disease in patients with normal resting left ventricular contractility.

A new nonexercise test to detect significant coronary disease was prospectively evaluated in 36 patients with chest pain syndrome and normal left ventricular contractility. Transesophageal atrial pacing was used to provoke ischemia during monitoring of left ventricular contractility by transesophageal echocardiography. A 12-lead ECG was recorded. A TSE was abnormal if new segmental wall motion abnormalities developed. On the basis of the TSE results, patients were separated into normal (group 1, n = 16) and abnormal response (group 2, n = 20). Arteriography revealed significant disease in 21 patients, 19 from group 2 and two from group 1. Sensitivity and specificity of TSE were 90% and 93%, respectively, and those for pacing ECG were 43% and 100%, respectively. In addition, TSE accurately predicted the coronary artery perfusion bed involved. In 10 patients, Wenckebach AV block developed during pacing and resolved immediately by the administration of atropine sulfate. No serious complications were seen. Thus TSE is a highly sensitive and specific novel technique to detect significant coronary disease in patients with chest pain syndrome and normal resting left ventricular contractility.

Aged↗
PubMed1991

Emergency coronary artery bypass surgery following failed balloon angioplasty: role of the internal mammary artery graft.

During a 4-year period (1986-1989), 3,502 patients had percutaneous transluminal coronary angioplasty (PTCA) in our institution. One hundred nineteen (3.4%) patients required emergency coronary artery bypass graft surgery (CABG) because of abrupt vessel closure following PTCA. Factors associated with vessel closure included lesion angulation greater than or equal to 90 degrees (p less than 0.007), the presence of thrombus (p less than 0.02), or a long (greater than or equal to 2 cm) lesion (p less than 0.03). Of these 119 emergency CABG patients, 108 (91%) arrived in the operating room in a stable condition (group I) and 11 (9%) were in cardiogenic shock (group II). Five (45%) of the group II patients were admitted to the hospital with an acute myocardial infarction and all 11 patients had a higher incidence of multivessel disease (p less than 0.05) and lower left ventricular ejection fraction (p less than 0.001) than group I patients. The overall surgical mortality was 10.1%; however, in group I the mortality was 5.6% and in group II it was 54.5% (p less than 0.001). The vessel that abruptly closed ("culprit vessel") was the left anterior descending (LAD) in 60%, the right coronary artery in 27%, and the left circumflex in 13%. The internal mammary artery was utilized to bypass the culprit artery in 51 (43%) patients, including 50% of the culprit LADs. With group I culprit LAD patients, when the left IMA was the bypass conduit, there were no hospital deaths nor strokes and there was a 6.3% incidence of perioperative infarction.

Adult↗
PubMed1991

Clustering of colorectal neoplasia: characteristics of coexisting adenomas in patients with severely dysplastic polyps or invasive (malignant) polyps as compared to patients with benign adenomas or carcinomas.

This study compared the size, histology and morphology of coexisting neoplastic polyps found in colonoscopy, and evaluated the clustering of these polyps in patients with either colorectal carcinoma, cancerous polyps or benign adenomas. Patients were divided by their most malignant form of neoplasia: Group A included 58 patients with early invasive cancerous polyps, and Group B included 73 patients with in situ carcinoma within an adenoma. Group C consisted of 335 patients with benign adenomas, and Group D had 289 patients with colorectal carcinoma. There were no significant differences between the four groups regarding sex, age and ethnicity. The cancerous polyps were significantly larger than the benign polyps. There were significantly (P less than 0.01) more patients with multiple (greater than or equal to 5) colonic lesions in Groups A or B than in Groups C or D. Coexisting polyps were much closer to the index growth, and demonstrated more severe dysplastic changes in the case of cancerous polyps than those associated with benign polyps or cancer. Based on our data we speculate that cancerous polyps are not merely a middle link in adenoma-carcinoma sequence, but rather mark a subset of patients who are especially prone to develop neoplastic changes in their colonic mucosa. These patients should be included in a more strict colonoscopic surveillance programme.

Adenocarcinoma↗
PubMed1990

Effects of caffeine ingestion on body fluid balance and thermoregulation during exercise.

This study investigated the effects of caffeine supplementation on thermoregulation and body fluid balance during prolonged exercise in a thermoneutral environment (25 degrees C, 50% RH). Seven trained male subjects exercised on a treadmill at an intensity of 70-75% of maximal oxygen consumption to self-determined exhaustion. Subjects exercised once after caffeine and once after placebo ingestion, given in a double-blind crossover design. Five milligrams per kilogram body weight of caffeine followed by 2.5 mg.kg-1 of caffeine were given 2 and 0.5 h before exercise, respectively. Rectal temperature was recorded and venous blood samples were withdrawn every 15 min. Water loss and sweat rate were calculated from the difference between pre- and post-exercise body weight, corrected for liquid intake. Following caffeine ingestion, when compared with placebo, no significant difference in final temperature or in percent change in plasma volume were found. No significant differences were observed in total water loss (1376 +/- 154 vs. 1141 +/- 158 mL, respectively), sweat rate (12.4 +/- 1.1 vs. 10.9 +/- 0.7 g.m-2.min-1, respectively), rise in rectal temperature (2.1 +/- 0.3 vs. 1.5 +/- 0.4 degrees C, respectively), nor in the calculated rate of heat storage during exercise (134.4 +/- 17.7 vs. 93.5 +/- 22.5 W, respectively). Thus, in spite of the expected rise in oxygen uptake, caffeine ingestion under the conditions of this study does not seem to disturb body fluid balance or affect thermoregulation during exercise performance.

Adult↗
PubMed1989

Balloon dilatation of symptomatic subacute intimal dissection presenting as restenosis.

Repeat percutaneous transluminal coronary angioplasty (PTCA) for subacute intimal dissections that produce symptoms after a period of 1 month or more is reluctantly performed for fear of extension and abrupt closure. Patients were identified with demonstrated intimal dissections (intimal contrast staining or frank intimal flap) at the time of initial PTCA who returned a mean of 17.5 weeks (range 9 to 50) later with recurrent chest pain. Repeat angiography revealed luminal compromise due to dissection rather than restenosis in 22 patients. Of these, 17 underwent repeat PTCA. Elective bypass surgery without attempted PTCA was chosen in the other 5 patients because of extensive intimal dissections (greater than 2 balloon lengths) or involvement of critical branches. In the group of 17 patients who had repeat PTCA, 10 (group 1) had a frank intimal flap without persistent contrast staining after the initial PTCA, while 7 (group 2) had both persistent staining and a flap. Successful PTCA was performed in 13 of these 17 patients (76%). There were 2 abrupt closures and 2 unsatisfactory luminal openings. One of these patients required urgent coronary bypass surgery. All 10 group 1 patients had successful repeat procedures versus only 3 of 7 group 2 patients (p = 0.01). The 3 patients with the greatest degree of luminal compromise immediately after the initial PTCA had failed repeat PTCA attempts. These results suggest that repeat PTCA for subacute intimal dissections presenting as restenosis can be successfully performed in selected patients, and that the presence of contrast staining and the degree of luminal compromise by the dissection may be predictive of outcome.

Aged↗
PubMed1989

Hepatic metastases: liposomal Gd-DTPA-enhanced MR imaging.

Liposomal gadolinium diethylenetriaminepentaacetic acid (DTPA) encapsulated within 70- and 400-nm vesicles was tested as a contrast agent for magnetic resonance (MR) imaging of the liver in rats with hepatic metastases. Liposomal Gd-DTPA caused significant improvement in contrast between liver and tumor (P less than .005) on T1-weighted MR images. Smaller 70-nm liposomal Gd-DTPA vesicles caused greater contrast enhancement, reflecting the larger surface-area-to-volume ratio of the smaller vesicles. Liposomal Gd-DTPA-enhanced images permitted significant improvement in metastasis detection by five blinded radiologists (P less than .005). By comparison, free Gd-DTPA without liposomes caused a statistically significant reduction in contrast between tumor and liver and reduced lesion detection (P less than .01). Liposomal Gd-DTPA also resulted in sustained vascular enhancement for 1 hour after administration. The results suggest that paramagnetic liposomes may become a useful MR imaging contrast agent.

Animals↗
PubMed1988

External load can alter the energy cost of prolonged exercise.

The present study was undertaken to examine the energy cost of prolonged walking while carrying a backpack load. Six trained subjects were tested while walking for 120 min on a treadmill at a speed of 1.25 m.s-1 and 5% elevation with a well fitted backpack load of 25 and 40 kg alternately. Carrying 40 kg elicited a significantly higher (p less than 0.01) energy cost than 25 kg. Furthermore, whereas carrying 25 kg resulted in a constant energy cost, 40 kg yielded a highly significant (p less than 0.05) increase in energy cost over time. The study implies that increase in load causes physical fatigue, once work intensity is higher than 50% maximal work capacity. This is probably due to altered locomotion biomechanics which in turn lead to the increase in energy cost. Finally, the prediction model which estimates energy cost while carrying loads should be used with some caution when applied to heavy loads and long duration of exercise, since it might underestimate the actual energy cost.

Adult↗
PubMed1988

Complications of gastrostomy.

Despite its simplicity, gastrostomy has been associated with a relatively high incidence of complications. We have described two unusual complications: inadvertent duodenostomy, resulting in gastric outlet obstruction, and the migration of a gastrostomy feeding tube into the midportion of the jejunum, resulting in obstruction of the small bowel.

Aged↗
PubMed1987

Changes of white blood cell count during prolonged exercise.

Leukocytosis was postulated to accompany short- and medium-length exercise; in this report, we have studied the changes in leukocyte count during and following prolonged exercise. White blood cell (WBC) counts were obtained in 15 endurance-trained subjects before, during, and at a recovery period after an ultralong exercise (120 km march), lasting 24 h. WBC counts increased after 16 h march from a baseline value of 8.5 +/- 0.3 10(9) l-1 to 11.3 +/- 0.8 10(9) l-1 (P less than 0.05) and then declined to 7.1 +/- 0.9 10(9) l-1 after 24 h march with no further significant changes during 64 h of recovery. These observations were supported by previous findings in three separate marches performed by a second group (40, 70, and 120 km). A parallel increase in plasma creatine phosphokinase activity from 127 +/- 4.4 ul-1 to 539 +/- 106.3 ul-1 was observed after 16 h march (P less than 0.01), indicating muscle cell damage. Our findings suggest that in extremely long marches, WBC counts return to baseline values before exercise is terminated. This phenomenon may reflect WBC infiltration to damaged muscle tissue.

Adult↗