Angiology

In order to study whether the circadian rhythm of acute myocardial infarc tion (AMI) onset has any impact on the clinical outcome, in terms of enzymati cally estimated infarct size, circulatory arrest from ventricular tachyarrhyth mias, and in-hospital mortality, the authors studied a representative population of 10,791 AMIs treated in the same center between 1973 and 1987. In 6,763 cases (63%) the time of symptom onset was known. In these cases a major peak in AMI incidence was observed between 7:01 AM and 10:00 AM, and minor peaks at 12:01 noon, 3:01 PM-4:00 PM, and 8:01 PM-9:00 PM. In a set of multiva riate analyses including several clinical characteristics, symptom onset between 6:00 AM and 12:00 noon significantly predicted a greater infarct size, and symp tom onset between 12:00 AM and 6:00, AM was associated with a significantly lower risk of circulatory arrests from ventricular tachyarrhythmias. The time of symptom onset was not significantly associated with in-hospital mortality after adjustment for other clinical characteristics, including infarct size. The authors suggest that the time of day has an impact, not only on the incidence, but also on the severity of AMI and that the ability of beta blockers to blunt the morning increase in AMI incidence may possibly contribute to the beneficial secondary preventive effects of such drugs after AMI.

The influence of an intravenous push of lidocaine 1 mg/kg followed by 2 mg/min infusion on total QRS amplitude and R-to-S duration in leads V₂-V₄ of the electrocardiogram was studied in 11 patients who were hospitalized in the coronary care unit. A computerized system sampled the amplitude and timing of peak R and S waves of 1100 QRS complexes of leads V₂-V₄, starting two minutes before the first push of lidocaine. Curves of amplitude and R-to-S dura tion versus time were obtained in all patients. QRS amplitude in V₂ and V₃ increased significantly in 10 of 11 patients (p < 0.005). The mean voltage in crease for all patients was 0.1±0.07 millivolt. The authors also observed a mild prolongation of R-to-S duration (0.8±1.0 millisecond p < 0.02). This new find ing, obtained by a simple computerized system, may possibly have potential future practical clinical application as a feedback parameter for closed-loop control systems for the administration of lidocaine.

The authors examined 47 subjects affected by acute phlebothrombosis of the lower limbs by means of light-reflection-rheography (LRR). The diagnosis was based on the results of clinical, Doppler, and duplex scanner evaluations. The results were compared with those obtained in 30 healthy subjects (control group).

The LRR examinations were performed by two methods: the one consisting of a passive execution of postural movements of the limb, the other using the technique of plethysmographic venous occlusion.

The pathological LRR curves were characteristic for each type of disease and for the site of thrombosis and were different from the normal ones.

The results obtained show the usefulness of the method and it potential in studying the collateral circulation and the effects of different therapies.

Thromboangiitis obliterans (TAO) is an occlusive vascular disease tradition ally known to be almost exclusive to young male smokers. The disease was con sidered to be extremely rare in women, seen only as isolated, novel case reports in the literature. In the past decade, however, a dramatic increase in the inci dence of female TAO has been observed.

In this paper the authors report 7 cases of clinically and angiographically verified female TAO. The world literature in regard to the diagnostic criteria, changing incidence, and etiology is reviewed. They conclude that the increased use of tobacco among young women in the past two to three decades is responsi ble for this dramatic change.

Cellular and humoral immune responses to vascular components were stud ied in 10 patients with thromboangiitis obliterans (TAO), including 3 in the mild stage of the disease and 7 in the active or severe stage. In this study the authors used the following vascular components: collagen Types I, III, IV, and V; elas tin ; and laminin. The cell-mediate reactivity (CMR) to these proteins was mea sured with an antigen-specific proliferation of peripheral mononuclear cells and evaluated by the stimulation index (SI), which is the ratio of thymidine incorpo ration in the presence and in the absence of antigen. The humoral immunologic response (HIR) to these vascular components was measured by an enzyme- linked immunosorbent assay (ELISA) and evaluated by the optical density (OD) index, which is the ratio of optical density (OD) in the patients' serum to that in the healthy male controls' serum. The stimulation index of collagen Types I and IV was significantly higher in patients with TAO than in healthy controls (p < 0.02). CMR to collagen Type V, elastin, and laminin was high in patients with active or severe TAO as well. However, similar statistical differences in mild TAO did not exist in the CMR. The OD index in collagen Types I, IV, and V was statistically higher in the patients than in the healthy controls (p < 0.01).

These autoimmune epiphenomena to vascular components in TAO suggest that autoimmune mechanisms are related to vasculitis of TAO patients. When it is considered that CMR was found in active or severe TAO, but not in mild TAO, CMR does not seem to be the initiator of vasculitis. These differences in immune reactivities suggest that the autoimmune epiphenomena to the vascular components might be related to the exacerbation and perpetuation of TAO.

The authors report their experience with 30 adult patients with Budd-Chiari syndrome (BCS), which is a rare and serious disorder, characterized by hepatic outflow obstruction caused by many different conditions.

The diagnosis was based on the clinical data, ultrasonography (US), vena cavography and hepatic venography, computed tomography (CT), and liver bi opsy. Behçet's disease (BD) was found in 10 patients with BCS as an underlying disease. Two patients used oral contraceptive drugs, 2 had liver tumor hepato cellular carcinoma and liver lymphoma, and 1 patient had chronic lymphocytic leukemia. Despite full investigation, the authors could not find any obvious un derlying cause in the other 15 patients.

The results suggest that (1) BCS must be considered as a possible complica tion in patients with Behçet's disease when they have hepatomegaly even if there were no cardinal manifestations of the disease at the time of admission, and BD is the most common etiologic factor in BCS (33%) in Turkey, where the inci dence of Behçet's disease is relatively high. (2) Anti-aggregant treatment seems to be effective in many instances. (3) There were space-occupying lesion-like appearances in the liver of 7 cases by CT and US examination in the acute stage, and these disappeared on the follow-up CT and US in 5 patients but continued in 2. BCS should thus be differentiated from other liver lesions. (4) There were other great-vessel involvements in 43% of the cases, mostly venous, but only 1 pulmonary arterial occlusion.

Measurement of transcutaneous oxygen tension (TcPo₂) is a noninvasive and easily reproducible method for objectifying and quantifying exercise ischemia in patients with stage II occlusive arterial disease. This technique is also used at rest to evaluate the therapeutic effect of vasoactive treatments.

To objectively assess the effectiveness of a vasoactive treatment on the condi tions of tissue perfusion, a randomized double-blind study of ifenprodil tartrate versus placebo was performed in 20 patients, whose TCPo₂ was continuously measured while they walked on a treadmill.

Patients treated with ifenprodil improved significantly as compared with the placebo group, for both the half-hypoxia area, representing the overall evolu tion of the tissue ischemia (+34.9% and —16.0%, respectively, p=0.01), and the half-hypoxia recovery time, estimating the postexercise recovery time (+30.2% and —3.6%, respectively, p < 0.05).

This study confirms that the continuous measurement of TcPo₂ during the recovery phase after exercise represents an objective method for the evaluation and follow-up of patients with stage II intermittent claudication. The results enabled the objective assessment of ifenprodil efficacy on the evolution of tissue hypoxia.

Two normotensive pregnant women who developed cerebral hemorrhage during delivery are reported. The hematoma was small and subcortical in one and large and putaminal in the other. They had no history of hypertension, cerebrovascular disorders, or eclampsia. Cerebral angiography studied in one case revealed no abnormalities. Idiopathic cerebral hemorrhage during delivery without any evidence of vascular risk factors is discussed.

A thirty-one-year-old woman with long-standing mixed connective tissue dis ease and severe obliterative vasculopathy of the digits developed digital throm bosis of the first three digits of the left hand after using an electric blow dryer. The digits remained cool, cyanotic, and painful for thirty-six hours before medi cal evaluation. She was given 100 mg recombinant tissue plasminogen activator (TPA) intravenously. Within one hour the blood flow to the digits returned, accompanied by severe intermittent vasospasm of the digits. The thumb did not necrose; however, the second and third digits required amputation. No im provement was noted in the patient's baseline Raynaud's phenomenon or digital pressures of the uninvolved digits after TPA treatment. This case documents the usefulness of TPA for digital thrombosis in the setting of vasculopathy of con nective tissue disease. However, it does not support the utility of a single dose of TPA for severe Raynaud's phenomenon and recurrent digital ischemia in pa tients with connective tissue disease.

A twenty-three-year-old woman had an acute myocardial infarction during the early postpartum period successfully treated with intravenous strepto kinase. The possible mechanisms of postpartum myocardial infarction are re viewed, and the clinical implication for the use of streptokinase in this situation is discussed.

Complete recanalization was achieved by intra-aortic infusion of urokinase in a case of complete occlusion of the abdominal aorta. The patient was a fifty- nine-year-old man with atrial fibrillation, hypertension, and diabetes mellitus who was admitted because of intermittent claudication and pain in both lower extremities at rest. Angiography demonstrated complete obstruction of the ab dominal aorta, but the bilateral iliac arteries were visualized via collaterals. Urokinase was administered intra-aortically in a total dose of 1,200,000 U dur ing the first day and a total dose of 960,000 U during the second day. The aorta and the iliac arteries recanalized after this treatment, and complete recanaliza tion associated with disappearance of subjective symptoms was observed after one month of treatment with warfarin. The present case suggests the usefulness of intra-arterial infusion of urokinase for the treatment of complete occlusion of the abdominal aorta.

Tricuspid endocarditis was diagnosed in a sixty-four-year-old patient with Chagas' disease who had a permanent cardiac pacemaker and whose generator had been replaced five months before an infection in the pocket. The pacing system was replaced by an epicardial one and the patient received antibiotics with good results.

The authors present a case of gastric angiodysplasia with upper gastrointes tinal bleeding, associated with severe ischemic congestive cardiomyopathy.

In orthostatic hypotensive patients renin is reported to increase in response to head-up tilt unless the lesion involves postganglionic sympathetic efferent nerves. The authors examined responses of plasma renin activity (PRA) to acute blood pressure reduction in 4 patients with orthostatic hypotension. When the coexistence of normal plasma norepinephrine (PNE) and normal or high-nor mal pressor response to alpha stimulant is considered to be a sign of preserved function of postganglionic fibers, 2 of the patients had sympathetic lesions mainly confined to central and/or preganglionic fibers. They were diagnosed as having multiple system atrophy (MSA). The other 2 were diagnosed as having idiopathic orthostatic hypotension with possible postganglionic lesions. Al though 1 MSA patient showed an increase in PRA from 2.0 to 4.7 ng/mL/hr in response to the tilt, the other MSA patient showed no PRA response to the tilt. The head-up tilt did not provoke an apparent PRA response in patients with idiopathic orthostatic hypotension. The authors infused sodium nitroprusside (SNP) in the 3 patients whose PRA did not respond to the head-up tilt. The infusion decreased blood pressure by 40 mmHg or more, but PRA responses were inappropriately small or suppressed. In all cases, PNE did not respond at all to the head-up tilt and to the infusion of SNP. These findings suggest that possible preservation of postganglionic fibers does not necessarily indicate an intact responsiveness of PRA. The PRA profiling may not be an accurate pre dictor for the site of the fiber degeneration in orthostatic hypotension.