RECURRENT RHABDOMYOLYSIS PRECIPITATED BY ALCOHOL: A CASE REPORT WITH PHYSIOLOGICAL AND ELECTRON MICROSCOPIC STUDIES OF SKELETAL MUSCLE

The case history is reported of a male chronic alcoholic, aged 40 years, who presented with muscle cramps and weakness, the passage of a decreasing quantity of dark urine, and a past history of similar episodes, all of which followed periods of acute alcoholism. The diagnosis of rhabdomyolysis was confirmed by the demonstration of myoglobinuria and the histological findings in skeletal muscle. Management of the accompanying hyperkalæmia and acute renal failure was by a potassium-binding resin and mannitol diuresis. Physiological studies of forearm skeletal muscle revealed a decreased exercise ability, but a normal vascular and biochemical response to exercise and intra-arterial infusion of adrenaline. Intra-arterial infusion of alcohol caused a decrease in the blood flow through forearm muscle. Electron microscopic examination of skeletal muscle obtained during the acute attack revealed patchy cellular and mitochondrial damage. The latter appeared to precede myofibrillar damage, as normal myofibrils were found adjacent to injured mitochondria; but normal mitochondria were not found adjacent to damaged myofibrils. Without information about the degree of muscle ischæmia produced by alcohol or about the effects of ischæmia on the ultrastructure of skeletal muscle cells, it is not possible at present to determine whether rhabdomyolysis is caused by ischæmia or by some other mechanism.     

Treatment of venous thrombosis in antithrombin III deficient patients with concentrates of antithrombin III

Summary Two patients with familial antithrombin III deficiency developed deep venous thrombosis of the lower limb. The diagnosis of venous thrombosis was made by the indium labelled platelet technique which also allowed for the daily assessment of thrombus size. Each patient received treatment with Warfarin, subcutaneous heparin, and infusions of antithrombin III concentrates. The authors conclude that infusions of antithrombin III concentrates may be of value in limiting the extent of acute thrombosis in patients with a severe deficiency of this protein and may help prevent pulmonary embolism. The haemorrhagic risk of continuing modest doses of heparin with high dose ATIII therapy appears small. In addition to its value in the diagnosis of venous thrombosis the indium platelet technique may give an early indication of thrombus extension and may thus indicate the effectiveness of treatment.     

Is the Outcome of Coronary Stenting Worse in Elderly Patients?

Initial reports of percutaneous transluminal coronary angioplasty (PTCA) in the elderly (≥: 75 years) showed a significantly lower primary success rate, higher in-hospital mortality, and a higher risk of emergency or elective coronary artery bypass graft (CABG) compared to younger patients. There are few data concerning acute outcomes and clinical follow-up after the use of coronary stenting in the elderly compared to < the 75-year-old age group. We evaluated 82 elderly patients and 280 younger patients who received Palmaz-Schatz stents during 1995, at a time when high pressure deployment and antiplatelet therapy was routinely used. The success rate and acute major complications were not significantly different between the elderly and younger patients. Clinical events (death, myocardial infarction [MI], repeat PTCA, or CABG) during 6-month follow-up were also not significantly different. Coronary stenting in the elderly can be carried out with a high success rate and low incidence of acute major complications. Thus, short-term clinical outcomes in elderly patients appear similar to results obtained in younger patients.     

Studies of Alpha-2-Adrenoceptor Function in Abstinent Alcoholics

Hormonal, haemodynamic and subjective psychological responses to the intravenous infusion of clonidine were investigated in nine male alcoholics who had been abstinent for 5 weeks, and were compared with those of nine healthy controls. The growth hormone response to clonidine was significantly blunted in the abstinent alcoholics. Both baseline cortisol levels and the clonidine-induced cortisol decrease were significantly greater in the alcoholics than in controls. Blood pressure, pulse rate and psychological responses to clonidine were similar in both groups. These results indicate that some aspects of alpha-2-adrenoceptor sensitivity are persistently abnormal in alcoholics at least 5 weeks into abstinence.     

Epicardial Maps of Atrial Fibrillation After Linear Ablation Lesions

Maps of AF After Ablation. Introduction: The purpose of this study was to investigate the mechanisms by which atrial linear ablation lesions eliminate atrial fibrillation (AF).
Methods and Results: With an array of 112 unipole, epicordial maps of electrically induced AF in 6 dogs (acute group), self-sustained AF in 6 dogs (chronic group), and sinus rhythm and atrial pacing in 3 dogs (control group) were analyzed before and after creating linear radiofrequency ablation lesions in both atria that eliminated the AF. In the acute and chronic groups, activation maps showed multiple wavelets with complex patterns of activation and reentry during AF. Conduction velocity and the number, size, and complexity of wavelets did not change, whereas median fibrillatory cycle length increased with the number of linear lesions. In the control group, refractoriness and conduction velocity were unaffected by the number of lesions.
Conclusions: In these models of AF, linear lesions that eliminate AF increase the cycle length of AF without changing conduction velocity, number or size of wavelets, or complexity of activation patterns.     

Anatomy of the Coronary Sinus and Epicardial Coronary Venous System in 620 Hearts: An Electrophysiology Perspective

Anatomy of the Coronary Venous System . Introduction: Cannulation of the coronary sinus (CS) is a prerequisite for left ventricular (LV) pacing and certain ablation procedures. The detailed regional anatomy for the coronary veins and potential anatomic causes for difficulty with these procedures has not been established. Methods and Results: Therefore, we performed macroscopic measurements in 620 autopsied hearts (mean age 60 ± 23 years, 44% female). The CS was preserved for analysis in 96%. Sixty‐three percent had a Thebesian valve that covered the posterior aspect of the CS ostium with extension to the superior (50%) and inferior aspects (18%) and was obstructive with fenestrations in 3 specimens. Partial or near occlusive valves were present occasionally at the ostium of the great cardiac vein (Vieussens; 8%) and middle cardiac vein (5%). Ninety‐three percent had left atrial branches, and 41% had at least one branch with lumen > 3 French. For CRT lead placement, the mid‐lateral LV was accessible from the middle cardiac vein (20%), the left posterior vein (92%) or the anterior interventricular vein (86%). Among specimens where the left phrenic nerve was preserved it crossed the LV mid‐lateral wall in 45%. Conclusions: Epicardial coronary vein anatomy is variable, and the mid‐lateral LV wall can potentially be accessed through various tributaries of the epicardial veins. The orientation of the Thebesian valve favors cannulation of the CS from an anterior (ventricular) and inferior approach. Anterobasal, mid‐lateral, and inferior apical LV coronary veins lie in proximity to the course of the phrenic nerve. (J Cardiovasc Electrophysiol, Vol. 24, pp. 1‐6, January 2013)