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S Yazdanfar

Publications and source records attributed to S Yazdanfar.

36 records · Page 2Linked to original sources
PubMed1994

Intravascular ultrasound for angiographically indeterminant left main coronary artery disease.

The precise diagnosis of the presence of significant left main coronary artery disease has profound prognostic and therapeutic implications. Coronary cineangiography has shown to be imprecise and inaccurate to determine the percent stenosis of the left main coronary artery. We report a case with significant left main coronary artery disease in whom coronary cineangiography was in discordance with the clinical data and intravascular ultrasonography. Based on the intravascular ultrasound findings, the patient underwent coronary artery bypass graft surgery. Therefore, the intravascular ultrasonography may be the procedure of choice for assessing indeterminant left main coronary artery lesions by coronary angiography.

Coronary Angiography↗
PubMed1993

Parallel angioplasty dilatation catheter and guide wire: a new technique for the dilatation of calcified coronary arteries.

Percutaneous transluminal coronary angioplasty (PTCA) of heavily calcified rigid coronary arteries has decreased success and increased complication rates. Three cases are presented describing a new technique for the dilatation of severely calcified coronary arteries that were not dilatable by conventional angioplasty methods. This technique involves the use of a balloon dilatation catheter system parallel to a guide wire.

Aged↗
PubMed1991

Bilateral coronary artery to left ventricular fistulas.

Congenital coronary artery fistulas are important coronary artery anomalies. Bilateral coronary artery fistulas are very rare and coronary artery to left ventricular communications are even more infrequent. This report describes a patient with bilateral right and left coronary artery fistulas draining into a common channel and emptying into the left ventricular cavity.

Aged↗
PubMed1987

High risk percutaneous transluminal coronary angioplasty in the treatment of severe coronary artery disease.

We report on 27 "high risk" patients out of 171 consecutive patients undergoing percutaneous transluminal coronary angioplasty from June 1984 to August 1985. The ages ranged from 31-80 years (mean 62.7 +/- 10) years. High risk percutaneous transluminal coronary angioplasty was defined as: salvage cases (3 patients) where the patients presented in cardiogenic shock or the vessels were not bypassable; multivessel coronary artery disease (22 patients) where a large area of jeopardized myocardium was dependent on the angioplasty vessel(s); left ventricular dysfunction (7 patients) as defined by two of the three criteria: left ventricular end-diastolic volume index greater than 100 ml/m2; ejection fraction less than 30%; and left ventricular end-diastolic pressure greater than 20 mm Hg. The initial success rate in the high risk patients was 85.2%. Emergency coronary artery bypass surgery in these patients was 7.4%. There was one death in the high risk group, as one of the salvage cases died 24 hours after successful percutaneous transluminal coronary angioplasty due to severe underlying myocardial disease. In conclusion percutaneous transluminal coronary angioplasty can be successfully performed in high risk patients with a low complication rate and should be considered as an alternative to coronary artery bypass graft surgery in selected high risk patients.

Adult↗
PubMed1987

Preliminary evaluation of cocarboxylase on myocardial protection of the rat heart.

The presence of cocarboxylase (CC) is essential for the oxidation of pyruvate to acetylcoenzyme A (acetyl-CoA) and its subsequent degradation by means of the Krebs cycle. We compared the effects of various concentrations of CC in a cardioplegic solution on the survival and hemodynamic and metabolic recovery of 23 isolated, working rat hearts subjected to 60 minutes of hypothermic (23 degrees C) ischemic arrest. Group 1 (N = 6) consisted of hearts infused with the basic cardioplegic solution (Tyers' solution with glucose), to which no CC was added. In group 2 (N = 6) CC was added at 0.1 ml/L to the cardioplegic solution. In group 3 (N = 5) CC was added at 1 ml/L, and in group 4 (N = 6) CC was added at 10 ml/L. The cardioplegic infusions were performed at a pressure of 40 mm Hg for 2 minutes just before arrest; 30 minutes later they were performed again for 1 minute. Only two hearts (33.3%) recovered in group 1 whereas five recovered in group 2, five (100%) in group 3, and five (83.3%) in group 4. The recovery of hemodynamic performance as a percentage of preischemic control values showed marked improvement in the CC groups, especially group 3, when compared with group 1. The metabolic variables in the CC groups were also markedly improved, with significantly (p less than .05) decreased levels of tissue lactate and increased levels of creatine phosphate compared with those in group 1.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1987

Beneficial effects of cocarboxylase in the treatment of experimental myocardial infarction in dogs.

Cocarboxylase, or thiamine pyrophosphate, is an essential coenzyme in the catabolism of pyruvate. The authors evaluated the effects of a stable cocarboxylase solution in the treatment of an experimentally created acute myocardial infarction in 14 healthy mongrel dogs. The left anterior descending artery was ligated for 60 minutes and data were collected at the following points: A) prior to ligation, B) 15 minutes after ligation, C) 30 minutes after ligation, and D) 60 minutes after ligation. In one group (Group II), cocarboxylase (150 mgm/kg) was given systematically via a central line 15 minutes and 45 minutes after ligation, while in Group I an equal amount of D5W was given. Hemodynamic data include heart rate, systolic and mean arterial pressure, pulmonary wedge pressure, right arterial pressure, and cardiac output. Myocardial O2 consumption was determined by the method of Rooke and Feigl. Electrocardiographic data were also monitored throughout the experiment. In both groups, preligation (point A) hemodynamic data were similar. In Group II, there were beneficial hemodynamic changes versus Group I (expressed as percentage recovery of hemodynamic performance from preligation) at points C and D, with significant (P less than 0.05) decreases in heart rate, increased stroke volume, decreased systemic vascular resistance, and decreased myocardial O2 consumption. EKG criteria also showed improvement in Group II versus Group I. In conclusion, this experiment suggests that cocarboxylase may be beneficial to ischemic canine myocardium by virtue of its favorable systemic hemodynamic effects.

Animals↗
PubMed1984

Ergonovine provocative testing: description of a "double catheter technique".

Since coronary arteries should be immediately accessible during ergonovine provocative testing (EPT), a double catheter technique is described. Using the catheter sheath technique from the right and left femoral arteries, right and left Judkins' catheters are introduced into each femoral artery. Selective coronary cineangiography during EPT is thus rapidly performed without the delay of exchanging catheters. Should coronary arterial spasm occur during the test, nitroglycerin can be administered into the coronary artery without delay.

Cardiac Catheterization↗
PubMed1983

Iatrogenic postoperative left ventricular outflow tract obstruction.

A 56-year-old female, who underwent aortocoronary bypass graft for occlusion of anterior descending artery is reported, who postoperatively developed a harsh systolic murmur, mitral regurgitation, and intraventricular systolic pressure gradient suggestive of hypertrophic subaortic stenosis. The above findings were due to the administration of dobutamine hydrochloride for hypotension in association with afterload reduction (intra-aortic balloon pumping) and disappeared almost immediately after left ventriculography (volume load).

Aortic Stenosis, Subvalvular↗
PubMed1977

Recuperative potential of cardiac muscle following relief of pressure overload hypertrophy and right ventricular failure in the cat.

This study examined the recuperative potential of cat hearts subjected to experimental right ventricular pressure overload (for a 10- to 14-day period) which provoked hypertrophy with and without congestive heart failure. Five groups of cats were studied: normal controls; one group with 70% pulmonary artery constriction which produced right ventricular hypertrophy (RVH); one group with an 87% constriction which also produced right ventricular hypertrophy but with congestive heart failure (CHF); and two groups which had been similarly subjected to pressure overload but which had been allowed a recovery period of 30 days after relief of the pressure overload. Both the 70% and 87% pulmonic constrictions were associated with extensive right ventricular hypertrophy, depression of myocardial contractile function, and severe redlction of cardiac norepinephrine stores (normal, 1.42 mug/g: RVH, 0.11 mug/g; CHF, 0.01 mug/g). After a 30-day period of relief from the pulmonic constriction normal hemodynamic function returned. In cats in which RVH had been relieved, right ventricular weight and contractile function were normal but catecholamine depletion persisted. Cats with relieved CHF showed depressed contractile function and depleted myocardial norepinephrine, and the right ventricular weight did not return to normal. Cardiac muscle of all pressure-overloaded nonrelieved hearts showed depressed velocity of shortening and depressed ability to sustain load. Cats with RVH alone regained normal muscle shortening velocity and load-bearing ability after relief. However, cardiac muscle from the CHF-relieved group recovered only unloaded shortening velocity while the ability to sustain load remained depressed. We conclude that the recuperative potential of myocardium damaged by pressure overload is adequate provided congestive heart failure has not occurred. Heart failure produces a persistent reduction in force-generating ability of the myocardium. Hypertrophy due to pressure overload, with or without CHF, leads to cardiac catecholamine depletion which is not readily reversed by relief of the overload.

Animals↗
PubMed1975

Myocardial metabolic studies in prolapsing mitral leaflet syndrome.

Patients with prolapsing mitral leaflet syndrome (PML) frequently have chest pain of undetermined etiology. Twenty-three patients with PML underwent cardiac hemodynamic, angiographic, and metabolic studies. The latter were performed during control spontaneous heart rate and tachycardia by right atrial pacing. Myocardial supply-demand ratio (DPTI:SPTI) was estimated from the planimetric integration of the diastolic area (diastolic pressure time index = DPTI) and systolic area (systolic pressure time index = SPTI) of the central aortic pressure. Chest pain during pacing occurred in five patients. In two patients, it was associated with ST depression typical of ischemia on the electrocardiogram. Myocardial lactate abnormalities (lactate production or less than 10% extraction) occurred in seven patients during pacing tachycardia and was present in two patients during control state. DPTI:SPTI ratio during control state was 1.22 (+/- 0.07 SE) and decreased to 0.85 (+/- 0.05 SE) during pacing tachycardia. It is concluded that the myocardial lactate abnormalities in PML, which were present in approximately 30% of the patients in the present series, are most likely due to myocardial hypoxia. Whether or not the hypoxia is secondary to "small vessel disease" is not elucidated by this study.

Adult↗
PubMed1975

Iatrogenic arteriovenous fistula: a complication of percutaneous subclavian vein puncture.

A case of iatrogenic subclavian arteriovenous fistula is reported. An intracath had been inserted percutaneously into the left subclavian vein to monitor the central venous pressure during aortic valve surgery. On the second postoperative day a thrill and continuous murmur were detected at the left subclavian region. Left subclavian arteriogram and catheterization studies confirmed the diagnosis of subclavian arteriovenous fistula. The lesion was treated surgically with satisfactory results.

Aortic Valve↗
PubMedDate not supplied

Percutaneous transluminal coronary angioplasty of the "very proximal" coronary artery stenosis.

We report on 11 patients with "very proximal" lesions out of a total of 300 consecutive patients who underwent percutaneous transluminal coronary angioplasty (PTCA). Eight patients had native left anterior descending (LAD) lesions and three had LAD saphenous vein grafts lesions. Lesions were considered to be "very proximal" when one half or more of the balloon was inflated in the left main coronary artery for the native LAD lesions or the aorta for the LAD coronary artery saphenous vein bypass graft (CABG) lesions. There was a mean reduction in stenosis from 88.3% (range 75-99) to 13.8% (range 0-60) and a mean reduction in transtenotic gradient from 47.2 mmHg (range 20-80) to 8.3 mmHg (range 0-20). The initial success rate was 90.9% (10 out of 11 patients) with a partial success in the other patient. No complications occurred in any of the patients. Two patients had restenosis (18.2%) at 3 months and 6 months, respectively, post-PTCA. It is concluded that "very proximal" lesions can be successfully dilated with a high initial success rate and low complication rate. Nevertheless, these lesions may present problems with guiding catheter stability and, because of the potential risk of circumflex (CX) occlusion, this vessel may have to be protected with a second guidewire.

Aged↗