Moshe Gueron

Echocardiographic and radionuclide angiographic observations following scorpion envenomation by Leiurus quinquestriatus.

The echocardiographic and radionuclide angiographic abnormalities in children after scorpion envenomation with L. quinquestriatus, were evaluated. Five children were severely hypertensive, one of them in respiratory failure and another had pulmonary edema. The results revealed poor global contractility 12-15 hr after the sting in three patients. The radionuclide angiograms also revealed poor contractility with low ejection fraction. There was enzymatic evidence of myocardial damage. The changes observed in the echocardiograms and radionuclide angiograms were attributed to catecholamine induced myocardial ischemia. The abnormalities observed suggest that systolic dysfunction plays a role in the pathogenesis of heart failure in scorpion envenomation, in addition to a decrease of left ventricular compliance and increased impedance to left ventricular emptying. The beneficial effects of nifedipine in hypertension and other cardiovascular manifestations justify the routine use of afterload reduction in children with cardiovascular manifestations after scorpion envenomation.

Renin and aldosterone levels and hypertension following envenomation in humans by the yellow scorpion Leiurus quinquestriatus

Renin activity and aldosterone blood levels were measured in ten patients following scorpion envenomation by the scorpion Leiurus quinquestriatus. All patients were hypertensive on admission, with clinical signs of systemic intoxication. The blood renin and aldosterone levels were elevated in all ten patients. The observation of high blood pressure and elevated levels of renin suggests that in addition to increased circulating catecholamines following scorpion envenomation, sympathetically induced renin release may play an important role in the pathogenesis of hypertension. This observation re-emphasizes the importance of afterload reduction in the treatment of the cardiovascular manifestations of scorpion envenomation.

Spontaneous Closure of a Traumatic Ventricular Septal Defect after Blunt Trauma Documented by Serial Echocardiography

A ventricular septal defect (caused by blunt chest trauma) that closed spontaneously over a period of 5 years was documented by serial echo-Doppler examinations. The shunt was relatively small and the patient was without symptoms from the time the lesion was discovered until its closure. In the absence of cardiac decompensation or pulmonary hypertension, a conservative approach, including serial echo-Doppler examinations, can be justified.

Abnormal coronary perfusion in experimental scorpion envenomation.

Perfusion defects and left ventricular dilation after experimental scorpion envenomation were evaluated in five dogs. Left Left ventricular dilation was observed in three dogs and right ventricular dilation in one other, in scans immediately after envenomation. Perfusion defects were inferred from scans in four dogs. The data are strongly suggestive of coronary hypoperfusion, and the mechanics of abnormal coronary flow after scorpion envenomation are discussed.

Coronary angiography in a patient with mirror-image heart (“situs inversus”)

A right-sided heart associated with mirror-image atrial arrangement (situs inversus) is a rare condition. The incidence of coronary arterial disease in this setting is probably similar to that in the general population. Description of coronary angiography in this condition is very rare. We have recently catheterized such a patient. The necessary approach to coronary angiography is emphasized.

Exaggerated blood pressure response at exercise in normotensive subjects: Demographic and stress performance characteristics

BACKGROUND Exercise testing is an important diagnostic and prognostic procedure in the assessment of patients with hypertension. An exaggerated blood pressure response to exercise among normotensive subjects was found to be one of the best predictors of future hypertension. The demographic characteristics of patients with an exaggerated blood pressure response during exercise have not been adequately described. METHODS AND RESULTS The demographic and stress performance characteristics of 2 groups of normotensive patients referred for exercise testing, one composed of patients with an exaggerated blood pressure response (group I, n=146) and a group of patients with a normal blood pressure response (group II, n=439) were prospectively compared. Patients in group I were older than those in group II (54+/-12 vs 51+/-13 years, P < .05). More men than women were found in both groups, yet significantly more in group I than in group II (83% vs 69% P < .001). Significantly more among the patients in group I had a higher level of education and were of Western origin than those in group II (P < .01). The resting systolic and diastolic blood pressures were higher in group I than in group II (131+/-18 vs 119+/-14 mm Hg, P< .001, and 81+/-8 vs 76+/-7 mm Hg, P < .001, respectively). The patients in group I achieved a higher percentage of the maximal predicted heart rate (88+/-7 vs 85+/-9 beats/min, P < .01). No significant differences were found between the groups in the duration of stress test and effort ischemia. CONCLUSIONS Patients with a hypertensive blood pressure response during stress testing have specific demographic and exercise characteristics.

The role of the intensivist in the treatment of the cardiovascular manifestations of scorpion envenomation.

The following report summarizes the role of the intensivist in the treatment of the cardiovascular manifestations of scorpion envenomation within the intensive care unit. It emphasizes the need for a clear understanding the mechanisms involved behind the manifestations of myocardial damage and the rational approach of aggressive treatment of the overstimulated autonomic nervous system. The report emphasizes the complexity of the clinical picture and the intensivist approach based on clinical and experimental evidence, with excellent results.

Systemic-pulmonary arteriovenous fistula of traumatic origin: A case report

Arteriovenous fistulas between the systemic circulation and the pulmonary artery are extremely rare. Continuous precordial murmur is the usual clinical sign while unilateral rib notching may be the only radiologic manifestation of this condition. Selective angiographic investigation is necessary to localize the site of such an arteriovenous (AV) fistula before surgery is performed. In a review of the literature of 15 published cases, the majority were of congenital origin, with four of these systemic-pulmonary AV fistulas of traumatic origin, of which one occurred after insertion of an intercostal catheter. We describe one case of traumatic origin 9 years after percutaneous thoracic drainage for spontaneous pneumothorax, in which transcatheter embolic occlusion of the feeding arteries of an AV fistula was attempted. The advantages and the disadvantages of the nonsurgical and surgical therapeutic approaches are discussed.

Patients with coronary collaterals and normal left ventricular systolic function: clinical, hemodynamic, and angiographic characteristics.

One hundred and twenty consecutive patients with significant coronary artery disease, normal left ventricular systolic function, and coronary collaterals were compared with 111 patients with the same characteristics but with no collaterals. No significant differ ences were found between the two groups in hypertension, diabetes mellitus, and smoking. The left ventricular end diastolic pressure was 16.4 ± 7 in the study group and 16.9 ±6.9 in the controls (NS). Significantly more diseased vessels were observed in the study group than in the control group (2.1 ±0.6 versus 1.7 ±0.6, p = < 0.001 ) . One hundred and one totally occluded vessels were found in the study group but only two in the control group. The richest collateral supply was to the right coronary artery: 94 sources to 85 diseased vessels (111%) including 66 sources to 52 totally occluded arteries (127%); to the left anterior descending: 59 sources to 89 diseased vessels (66%) including 37 sources to 33 totally occluded arteries (112%). The poorest supply was to the left circumflex: 17 sources to 69 diseased vessels (25%), including nine sources to 16 totally occluded arteries (56%). No collaterals were observed in 14 totally occluded vessels in the study group and in two of the controls, while the systolic function at rest was still normal. It is suggested that coronary collaterals are important in preserving left ventricular systolic and diastolic performance at least at rest. Not readily visible collaterals may also prevent systolic dysfunction.

Mid left anterior descending coronary artery originating from the right coronary artery

Dual connection of the left anterior descending coronary artery to the left and right coronary arteries is a very rare congenital anomaly. In this report we describe two cases in which the mid-position of the left anterior descending coronary artery is connected to the right coronary artery, one directly and the second by way of the infundibular artery. To the best of our knowledge, connection of the mid-position of the left anterior descending to the infundibular artery has not been previously described.