Several experimental studies have shown that levocarnitine reduces myocardial injury after ischemia and reperfusion by counteracting the toxic effect of high levels of free fatty acids, which occur in ischemia, and by improving carbohydrate metabolism. In addition to increasing the rate of fatty acid transport into mitochondria, levocarnitine reduces the intramitochondrial ratio of acetyl-CoA to free CoA, thus stimulating the activity of pyruvate dehydrogenase and increasing the oxidation of pyruvate. Supplementation of the myocardium with levocarnitine results in an increased tissue carnitine content, a prevention of the loss of high-energy phosphate stores, ischemic injury, and improved heart recovery on reperfusion. Clinically, levocarnitine has been shown to have anti-ischemic properties. In small short-term studies, levocarnitine acts as an antianginal agent that reduces ST segment depression and left ventricular end-diastolic pressure. These short-term studies also show that levocarnitine releases the lactate of coronary artery disease patients subjected to either exercise testing or atrial pacing. These cardioprotective effects have been confirmed during aortocoronary bypass grafting and acute myocardial infarction. In a randomized multicenter trial performed on 472 patients, levocarnitine treatment (9 g/day by intravenous infusion for 5 initial days and 6 g/day orally for the next 12 months), when initiated early after acute myocardial infarction, attenuated left ventricular dilatation and prevented ventricular remodeling. In treated patients, there was a trend towards a reduction in the combined incidence of death and CHF after discharge. Levocarnitine could improve ischemia and reperfusion by (1) preventing the accumulation of long-chain acyl-CoA, which facilitates the production of free radicals by damaged mitochondria; (2) improving repair mechanisms for oxidative-induced damage to membrane phospholipids; (3) inhibiting malignancy arrhythmias because of accumulation within the myocardium of long-chain acyl-CoA; and (4) reducing the ischemia-induced apoptosis and the consequent remodeling of the left ventricle. Propionyl-L-carnitine is a carnitine derivative that has a high affinity for muscular carnitine transferase, and it increases cellular carnitine content, thereby allowing free fatty acid transport into the mitochondria. Moreover, propionyl-L-carnitine stimulates a better efficiency of the Krebs cycle during hypoxia by providing it with a very easily usable substrate, propionate, which is rapidly transformed into succinate without energy consumption (anaplerotic pathway). Alone, propionate cannot be administered to patients in view of its toxicity. The results of phase-2 studies in chronic heart failure patients showed that long-term oral treatment with propionyl-L-carnitine improves maximum exercise duration and maximum oxygen consumption over placebo and indicated a specific propionyl-L-carnitine effect on peripheral muscle metabolism. A multicenter trial on 537 patients showed that propionyl-L...

Background-Tumor necrosis factor alpha-␣ (TNF-␣) activation is an independent prognostic indicator of mortality in patients with heart failure (HF). Despite the recognition that several TNF family cytokines are elevated during myocardial infarction, their role in predicting subsequent prognosis in these setting remains poorly understood. Methods and Results-We performed a systematic evaluation of TNF-␣ and its type 1 and 2 soluble receptors, together with interleukin (IL)-6, IL-1 receptor antagonist, and IL-10, in 184 patients (132 men; mean age, 64Ϯ12) consecutively admitted for myocardial infarction. We correlated their values to short-and long-term incidence of death and HF (primary outcome). In 10 patients, we also studied the presence of transcardiac gradients for TNF-␣ and its soluble receptors. The control group comprised 45 healthy subjects who were sex and age matched (33 men; mean age, 65Ϯ6 years) to the patients. All tested cytokines were increased in patients, and no transcardiac or systemic AV difference was found. After a median follow-up of 406 days (range, 346 to 696 days), 24 patients died and 32 developed HF. Univariate analysis showed that all cytokines were related to outcome, whereas after adjustment for baseline and clinical characteristics, sTNFR-1 remained the only independent predictor of death and HF (hazard ratio, 2.9; 95% CI, 1.9 to 3.8, tertile 1 versus 3), together with left ventricular ejection fraction, Killip class, and creatine kinase-MB at peak. Conclusions-sTNFR-1 is a major short-and long-term predictor of mortality and HF in patients with acute myocardial infarction. (Circulation. 2005;111:863-870.)

We postulate that an important unrecognised factor in the development of Tako-Tsubo cardiomyopathy is the presence of abnormal myocardial functional architecture (such as localised mid-ventricular septal thickening), which in the presence of dehydration and/or raised catecholamine levels due to physical or emotional stress, leads the development of a severe transient LV mid-cavity obstruction. This effectively sub-divides the LV into two functionally different chambers with a marked increase in wall stress in the high pressure distal apical chamber. This, in combination with the abnormal high circulating catecholamine levels, induces widespread sub-endocardial ischaemia which is unrelated to a specific coronary artery territory. With rehydration/fall in catecholamine levels the interventricular gradient resolves and distal function recovers. Low dose SR/S DSE confirms that the distal ischaemic substrate is myocardial stunning.