Gigantic arteriovenous fistula between left coronary cusp and coronary sinus draining into the right atrium.

Coronary arteriovenous fistulas (CAF) are infrequent anatomic anomalies that establish a direct connection between coronary arteries and cardiac chambers. The reported incidence is extremely low and estimated at 0.002% in the general population. We report a rare case of CAF in a middle-aged man, who was asymptomatic but incidentally found to have a gigantic CAF on a low-dose Computed Tomography scan of his chest. The case was presented to cardiothoracic surgeons. Since the patient was asymptomatic, they recommended medical management and continued close surveillance. The Left Coronary Artery or its branches are extremely uncommon site for CAF. With the advances in technology, the network of veins including coronary sinus has gained further clinical relevance. While technology has helped elucidate many aspects of these rare anomalies, mysteries still remain. With continued research, we can expect more cost-effective and less invasive interventional therapies to be developed in the near future.

Platelet Count and Mean Platelet Volume at the Time of and After Acute Myocardial Infarction.

Platelet count has been shown to be lower and mean platelet volume (MPV) to be higher in acute myocardial infarction (MI). However, it is not known whether these changes persist post-MI or if these measures are able to distinguish between acute thrombotic and non-thrombotic MI. Platelet count and MPV were measured in 80 subjects with acute MI (thrombotic and non-thrombotic) and stable coronary artery disease (CAD) at cardiac catheterization (acute phase) and at >3-month follow-up (quiescent phase). Subjects were stratified using stringent clinical, biochemical, histological, and angiographic criteria. Outcome measures were compared between groups by analysis of variance. Forty-seven subjects met criteria for acute MI with clearly defined thrombotic (n = 22) and non-thrombotic (n = 12) subsets. Fourteen subjects met criteria for stable CAD. No significant difference was observed in platelet count between subjects with acute MI and stable CAD at the acute or quiescent phase. MPV was higher in acute MI (9.18 ± 1.21) compared to stable CAD (8.13 ± 0.66; P = 0.003) at the acute phase but not at the quiescent phase (8.48 ± 0.58 vs 8.94 ± 1.42; P = 0.19). No difference in platelet count or MPV was detected between thrombotic and non-thrombotic subsets at acute or quiescent phases. The power to detect differences in these measures between thrombotic and non-thrombotic subsets was 58%. Higher MPV at the time of acute MI is not observed by 3 months post-MI (quiescent phase). Platelet count and MPV do not differ in subjects with thrombotic versus non-thrombotic MI. Further investigation is warranted to evaluate the utility of these measures in the diagnosis of acute MI.

Protease-Activated Receptor 1 Inhibitors: Novel Antiplatelet Drugs in Prevention of Atherothrombosis.

Protease-activated receptor (PAR)-1 inhibitors have recently become popular in the use of atherosclerosis among clinicians. Atherosclerosis can cause cardiovascular and cerebrovascular events leading to one of the major causes of mortality worldwide. Thrombin-mediated platelets can cause atherosclerotic plaques, and these platelets are activated by thrombin through the PAR-1. Vorapaxar and atopaxar are novel antiplatelet drugs that inhibit the thrombin-induced platelet activation by antagonizing the PAR-1. The objective of this article is to review the mechanism of action of vorapaxar and atopaxar and explain the rationale for using them in atherothrombosis patients including myocardial infarction, peripheral arterial disease, and stroke.

Circulating levels of plasminogen and oxidized phospholipids bound to plasminogen distinguish between atherothrombotic and non-atherothrombotic myocardial infarction.

Oxidized phospholipids (OxPL) are abundant in atherosclerotic plaques. They are also bound to circulating plasminogen after myocardial infarction (MI), and their binding to plasminogen may accentuate fibrinolysis. We sought to assess whether circulating levels of plasminogen and OxPL bound to plasminogen (OxPL-PLG) increase following acute MI and whether this increase differs between atherothrombotic (Type 1) and non-atherothrombotic (Type 2) MI. We measured circulating levels of plasminogen and OxPL-PLG at 0, 6, 24, 48 h, and >3 months (stable state) following acute MI and following an angiogram for stable coronary artery disease (CAD). Forty-nine subjects met the criteria for acute MI, of whom 34 had clearly defined atherothrombotic (n = 22) or non-atherothrombotic (n = 12) MI; 15 patients met the criteria for stable CAD. Mean baseline levels of plasminogen and OxPL-PLG were lower in the acute MI group than in the stable CAD group (9.75 vs 20.2, p < 0.0001 for plasminogen and 165.5 vs 275.1, p = 0.0002 for OxPL-PLG) and did not change over time or between time points, including the 3-month follow-up. Mean baseline levels of plasminogen and OxPL-PLG were also lower in atherothrombotic (Type 1) than in non-atherothrombotic (Type 2) MI subjects (8.65 vs 12.1, p < 0.03 for plasminogen and 164.5 vs 245.7, p = 0.02 for OxPL-PLG), and this relationship did not change over time or between time points. Plasminogen and OxPL-PLG were lower in patients presenting with an acute MI than in those with stable CAD and also in those with atherothrombotic MI (Type 1) vs. those with non-atherothrombotic MI (Type 2). These findings persisted at a median follow-up of 3 months post-MI. The association of plasminogen and OxPL-PLG with acute MI, particularly atherothrombotic MI (Type 1), could reflect a reduced fibrinolytic capacity, associated with an increased risk of atherothrombotic events differentiating stable CAD from unstable CAD and atherothrombotic MI (Type 1) from non-atherothrombotic MI (Type 2). Additional study with a larger sample size is warranted.

Aortic Atherosclerosis: A Common Source of Cerebral Emboli, Often Overlooked!

Aortic atherosclerotic plaques are usually seen in males older than 55 years who are known to have risk factors of atherosclerosis. Recent large series of consecutive stroke patients reported that the prevalence of aortic atheromatous plaques in patients with stroke is about 21%-27%, which is in the same magnitude when compared with the prevalence of carotid disease (10%-13%) and atrial fibrillation (18%-30%). Atheromatous plaques are composed of a lipid pool, a fibrous cap, smooth muscle cells, and mononuclear cell infiltration with calcification. Aortic plaques can cause embolization to brain, extremities, or visceral organs. Atheroembolization can occur spontaneously or as a result of manipulation during cardiac or vascular surgery. Only few cases of cerebral embolization from an aortic plaque in the absence of any manipulation have been described. Although few atherosclerotic plaques can be visualized on the aortogram, transesophageal echocardiogram remains a preferred modality for diagnosis in such cases. We present a case of cerebral embolism arising from a mobile noncalcified complex aortic arch plaque diagnosed on a transesophageal echocardiogram and review the literature on its diagnosis, clinical implications, and management.

Cardiac lipoma.

Lipomas of the heart are encapsulated tumors that are composed primarily of mature fat cells. Cardiac lipomas can originate either from subendocardium (approximately 50%), subpericardium (25%), or from the myocardium (25%) and may be located more frequently in left ventricle or right atrium. We report a 74-year-old female who presented with dyspnea on exertion and was found to have 5×5 cm mass occupying most of the right atrium on a transesophageal echocardiogram.

'Smoke in the air': a rare cerebrovascular cause of neurological signs and symptoms in a young adult.

Moyamoya disease is a rare neurological condition that affects children and adults of all ages. It is characterized by chronic, progressive stenosis of the circle of Willis that ultimately leads to the development of extensive collateral vessels. Presenting symptoms are usually due to cerebral ischemia or hemorrhage. The Japanese term moyamoya (meaning puffy or obscure) was coined to describe the characteristic 'smoke in the air' appearance of these vessels on cerebral angiography. Moyamoya has the highest recorded incidence in Japan (0.28 per 100,000). In the west it is an extremely rare condition with an overall incidence of (0.086 per 100,000) in the Western United States. Etiology for the most part is unknown; however, genetic susceptibility related to RNF213 gene on chromosome 17q25.3 has been suggested. Moyamoya is being diagnosed more frequently in all races with varying clinical manifestations. Moyamoya disease is a rare progressive neurologic condition characterized by occlusion of the cerebral circulation with extensive collaterals recruitment in children and adults. Distinguished radiological findings confirm the diagnosis. Early recognition and swift institution of therapy is vital in order to minimize neurological deficits. We present the case of a 19-year-old African American female who presented with left-sided parastheia, weakness, and headache for 2 days duration.

Stem cell therapy: promising treatment in heart failure?

Cardiac repair through the use of regenerative medicine has been a considerable research focus over the last decade. Several stem cell types have been investigated over this timeframe as potential candidates to target post-infarction heart failure. The progression of investigation through the rigors of clinical trial design has provided some answers as to the potential clinical utility of this therapy; although there are many questions that remain. This review will concentrate on the clinical trial results of stem cell therapy for cardiac repair since the turn of the century and discuss some of the points that need clarification before this form of therapy can be considered for widespread applicability.