Yedael Har-Zahav

Shoulo thrombolytic therapy be administered in the mobile intensive care unit in patients with evolving myocardial infarction? A pilot study

The growing recognition of the importance of early thrombolysis in evolving myocardial infarction was the basis for the present study, which evaluated the effectiveness, feasibility and safety of prehospital thrombolytic therapy. In a relatively small study, 118 patients were allocated to receive either prehospital treatment with recombinant tissue-type plasminogen activator (rt-PA) in the mobile intensive care unit (group A, 74 patients) or hospital treatment (group B, 44 patients). A total of 120 mg of rt-PA was infused over a period of 6 h. All patients were fully heparinized and underwent radionuclide left ventriculography and coronary angiography during hospitalization. Although group A was treated significantly earlier than group B after onset of symptoms (94 +/- 36 versus 137 +/- 45 min, respectively; p less than 0.001), no significant differences were observed between the groups in 1) extent of myocardial necrosis, 2) global left ventricular ejection fraction at discharge, 3) patency of infarct-related artery, 4) length of hospital stay, and 5) mortality at 60 days. However, a trend to a lower incidence of congestive heart failure at hospital discharge was observed in the prehospital-treated compared with the hospital-treated group (7% versus 16%, respectively; p = NS). No major complications occurred during transportation. It is concluded that myocardial infarction can be accurately diagnosed and thrombolytic therapy initiated relatively safely during the prehospital phase by the mobile intensive care team, thus instituting a beneficial clinical trend in favor of prehospital thrombolysis.

Subclavian Coronary Steal Syndrome: An Obligatory Common Fate between Subclavian Artery, Internal Mammary Graft and Coronary Circulation

The long-term patency of the left internal mammary artery (IMA) has made it the preferred conduit for myocardial revascularization. The proximal segment of the subclavian artery becomes functionally connected to the coronary circulation as a result of IMA implantation during coronary artery bypass surgery. The subclavian coronary steal syndrome results from stenosis in the left subclavian artery proximal to the IMA, compromising blood flow to the myocardium. We describe 7 patients, aged 55–75 years, 1.7–10.5 years after coronary bypass who presented with recurrent angina due to subclavian artery stenosis. The IMA graft was found open in each patient. A true steal mechanism was not demonstrated, casting doubt on the syndrome’s traditional name. Angioplasty and stenting of the subclavian artery resulted in the immediate disappearance of angina and continuous benefit at a follow-up of 3–32 months. The subclavian coronary steal syndrome, although rare, is a severe condition readily treated by angioplasty and stenting.

Double-helical CT as a new tool for tracking of allograft atherosclerosis in heart transplant recipients.

RATIONALE AND OBJECTIVES Tracking the progression of allograft atherosclerosis in heart transplant recipients is currently accomplished using invasive techniques. If its monitoring feasibility is demonstrated, spiral CT could be a non-invasive alternative for this objective. METHODS Twenty-four consecutive heart transplant patients (21 men, 3 women, mean age 55 +/- 11 years) were scanned using double-helical CT. The first scan was performed 1.9 +/- 1.3 years after transplantation. After 2 years of follow-up, 4 patients died and the remaining 20 underwent a second scan. All scans were performed according to a previously reported double-helical CT protocol. RESULTS The incidence of coronary calcification at the first scan was 4.2% (1/24); it increased to 40% (8/20) at the second scan (P < 0.001). Spiral CT identified new but very mild calcific deposits in seven patients with a mean total calcium score of 6.7 +/- 4.0. CONCLUSIONS Double-helical CT is a viable tool to diagnose and track newly developed allograft atherosclerosis.

Coronary calcium as a reliable tool for differentiating ischemic from nonischemic cardiomyopathy

In conclusion, the presence or absence of coronary calcium as detected by this rapid technique represents a simple and reliable noninvasive sign for the differential diagnosis between ischemic and nonischemic DC.

Left main coronary artery atresia : Extremely rare coronary anomaly in an asymptomatic adult and an adolescent soccer player

Left main coronary artery atresia is a very rare coronary anomaly with only 33 cases reported in the literature, of whom only 1 patient is asymptomatic. Pediatric patients are usually very symptomatic early in life (dyspnea, syncope, failure to thrive, ventricular tachycardia, and sudden death), whereas adult patients begin showing symptoms (angina or sudden death) only at an advanced age. Given the high risk related to the presence of left main coronary artery atresia, and in view of the good results obtained by coronary artery bypass surgery, coronary artery revascularization should always be considered as the possible treatment of choice for establishing adequate myocardial blood flow.

Coronary ostial stenosis after aortic valve replacement without coronary cannulation

Abstract Coronary ostial stenosis after aortic valve replacement (AVR) was attributed to trauma inflicted to the coronary ostia during coronary cannulation for selective coronary injection of cardioplegia fluid. 1–3 This report presents 2 cases who developed coronary ostial stenosis after AVR and in whom cannulation of the coronary ostia was not performed.

Prostaglandin E1 during angioplasty as preventative therapy for coronary restenosis.

The effect of intravenous prostaglandin E1 (PGE1) on the incidence of restenosis after elective percutaneous transluminal coronary angioplasty (PTCA) was studied in a prospective, single-blind, randomized trial of 30 patients. Group I (12 patients) received only the conventional medications before and after protocol, and group II (18 patients) received intravenous PGE1 influsion for 24 hours starting at least 2 hours before angiography after hemodynamically based titration to a mean dosage of 16 ± 3 ng/kg/min (range, 10–20 ng/kg/min). All patients received aspirin orally, beginning 24 hours before PTCA and continuing for 6 months, and intravenous heparin at 1000 U/h for 24 hours commencing with the beginning of catheterization before PTCA. Recatheterization was performed routinely at 6 months after PTCA, or earlier when clinically indicated. Angiographic evaluations were made by both visual and quantitative assessment. No significant side effects of PGE1 treatment were observed. Only 17% of patients treated by PGE1 experienced angina pectoris during 6-month follow-up period, as compared with 42% of patients who received conventional treatment (p = 0.13). Re-PTCA was more frequent in patients receiving conventional therapy than in those receiving PGE1 (42% versus 11%; p = 0.06). The use of PGE1 during PTCA was associated with 17% restenosis (both by computer and by visual evaluation) 6 months post-PTCA as compared with 33% and 50% restenosis (by computer and by visual evaluations, respectively) in the conventional group (p < 0.05). In conclusion, PGE1 appears to decrease coronary restenosis 6 months after PTCA.

The impact of gender mismatching on early and late outcomes following heart transplantation: Gender mismatching impacts heart transplantation outcomes

The role of donor/recipient gender matching on the long‐term rejection process and clinical outcomes following heart transplantation (HT) outcomes is still controversial. We aim to investigate the impact of gender matching on early and long‐term outcome HT.

Attenuated responses of doppler-derived hemodynamic parameters during supine bicycle exercise in heart transplant recipients

The aim of this study was to characterize Doppler-derived hemodynamic parameters in heart transplant recipients at rest and during symptom-limited supine bicycle exercise. Eighteen sedentary patients aged 54.0 ± 2 years, 1.6 ± 1.0 years following cardiac transplantation, and 18 sedentary healthy volunteers aged 51.8 ± 4 years were investigated. Basic hemodynamic parameters and Doppler-derived parameters were recorded at rest and at peak dynamic exercise. Resting heart rate, blood pressure and rate-pressure product were higher in the transplanted patients (p < 0.001). However, in comparison with the resting state, the increase in these parameters at exercise was lower in heart transplant recipients. In the healthy, dynamic exercise induced an increase in peak flow velocity, mean acceleration, flow velocity integral, stroke volume, cardiac output and cardiac index (p < 0.001 for all) while systemic vascular resistance, ejection time and acceleration time decreased (p < 0.001 for all). The following parameters increased in the transplanted patients at dynamic exercise: peak flow velocity, cardiac output and cardiac index (p < 0.001), mean acceleration (p < 0.01) and flow velocity integral (p < 0.05). Ejection time decreased (p < 0.05) and acceleration time and systemic vascular resistance remained unchanged. In conclusion, at rest peak flow velocity, mean acceleration, flow velocity integral and stroke volume are lower in the transplanted than in the healthy controls, while cardiac output, cardiac index and systemic vascular resistance are equal. Our study demonstrates attenuated responses of basic hemodynamic parameters and Doppler-derived cardiovascular indices at symptom-limited supine bicycle exercise in heart transplant recipients compared to healthy volunteers.

Blunted responses of Doppler-derived aortic flow parameters during whole-body heavy isometric exercise in heart transplant recipients

BACKGROUND Relatively light isometric exercise (handgrip) in heart transplant recipients induces attenuated increments in heart rate, blood pressure, and systemic vascular resistance, but hemodynamic response to whole-body, heavy isometric exercise is unknown. The aim of our study was to investigate the influences of whole-body, heavy, isometric exercise on Doppler-derived parameters in these patients. METHODS We investigated 18 patients, aged 54.0 +/- 2 years, 1.6 +/- 1.0 years after cardiac transplantation and 18 sedentary healthy volunteers, aged 51.8 +/- 4 years (p = not significant). Patients performed supine, isometric exercise by stretching a whole-body isometric device at 50% of maximal voluntary contraction for 3 minutes. RESULTS Resting heart rate, blood pressure, and rate-pressure product were higher in transplanted patients when compared with the healthy volunteers (p < 0.001 for all). However, during isometric exercise, these parameters increased to a lesser extent in the transplanted compared with the healthy subjects-heart rate, 12% vs 40% (p < 0.001); mean arterial pressure, 20% vs 27% (p < 0.05); and rate-pressure product, 39% vs 85% (p < 0.001). In the healthy volunteers, peak-flow velocity, mean acceleration, flow-velocity integral, and stroke volume decreased by 30% to 40% with isometric exercise (p < 0.001 for all), whereas systemic vascular resistance increased by 36% (p < 0.001) and cardiac output did not change. In the transplanted patients, all above parameters remained unchanged. Heavy, whole-body isometric exercise was well tolerated in heart transplant recipients in this study, without hemodynamic deterioration or other complications. CONCLUSIONS With whole-body, heavy isometric exercise, Doppler-derived aortic flow parameters demonstrate blunted responses or remain unchanged among heart transplant recipients. The observed phenomenon may have implications for studies of exercise physiology in transplant recipients.