Tamás Simor

Drugs, gene transfer, signaling factors: a bench to bedside approach to myocardial stem cell therapy

In the past few years, the dogma that the heart is a terminally differentiated organ has been challenged. Evidence from preclinical investigations emerged that there are cells, even in the heart itself, that may be able to restore impaired cardiac function after myocardial infarction. Although the exact mechanisms by which the infarcted heart can be repaired by stem cells are not yet fully defined, there is a new optimism among cardiologists that this treatment will prove successful in addressing the cause of heart failure after myocardial infarction—myocyte loss. Despite the promising preliminary data of human myocardial stem cell trials, scientists have also focused on the possibility of enhancing the underlying mechanisms of stem cell repair to gain healthier myocardial tissue. Attempts to induce neo-angiogenesis by transfecting stem cells with signaling factors (such as VEGF), to raise the number of endothelial progenitor cells with medical treatments (such as statins), to transfect stem cells with heat shock protein 70 (as a cardioprotective agent against ischemia) and to enhance the healing process after myocardial infarction with the use of various forms of stimulating factors (G-CSF, SCF, GM-CSF) have been made with notable results. In this article, we summarize the evidence from preclinical and clinical myocardial stem cell studies that have addressed the possibility of enhancing the regenerative capacity of cells used after myocardial infarction.

Radiofrequency catheter ablation of left ventricular outflow tract tachycardia with the assistance of the CartoSound system

Catheter ablation of left ventricular outflow tract tachycardia (LVOTT) holds the risk of complications, if foci are located close to the coronary artery orifices. The use of an accurate three-dimensional electro-anatomic approach is necessary to avoid ablation in the coronaries. We report a case in which we demonstrate the value of the CartoSound system, in the ablation of LVOTT.

Isolated spontaneous septal myocardial infarction

Isolated occlusion of the septal perforating branch of the left anterior descending coronary artery is extremely rare. As a result, little is known about its electrocardiographic manifestations compared with those of an anteroseptal myocardial infarction. We present the case of an isolated septal myocardial infarction with ST-segment elevation.

Chronic postinfarction pseudo-pseudoaneurysm diagnosed by cardiac MRI

Left ventricular pseudo‐pseudoaneurysm is an extremely rare complication of myocardial infarction. In this condition the postinfarction rupture of the myocardium is not transmural, but remains circumscribed within the ventricular muscle itself as a cavity joining to the left ventricle through a narrow neck. The differentiation between postinfarction pseudoaneurysms and pseudo‐pseudoaneurysms may be very difficult using conventional imaging techniques, such as transthoracic, or transesophageal echocardiography and left ventricular angiography. Cardiac MRI (CMR), however, is capable of distinguishing among anatomical structures such as pericardium, thrombus, and myocardium. In our report a chronic postinfarction pseudo‐pseudoaneurysm is described by CMR in a patient with an old myocardial infarction. J. Magn. Reson. Imaging 2007.

Ictal asystole: a systematic review

To comprehensively analyze ictal asystole (IA) on a large number of subjects.

Magnetic Resonance Imaging-Based Biventricular Pacemaker Upgrade

This report describes a patient with drug refractory severe chronic ischemic heart failure, atrial fibrillation with bradycardia, and left bundle branch block who had a failed implantation of a biventricular pacemaker because of a high left ventricular pacing threshold. VVI pacemaker implantation had not improved the patients condition. MRI‐guided biventricular pacemaker upgrade had been performed with a left ventricular epicardial lead at the lateral region where a 4‐mm thickening during systole had been proven. After 6 months of effective resynchronization, the patients functional class improved to NYHA II without further need of hospitalization. (PACE 2004; 27:1011–1013)

The role of cardiovascular magnetic resonance imaging in cardiac resynchronisation therapy

Abstract Cardiac electromechanical resynchronisation therapy (CRT) is an effective non-pharmacological treatment of patients suffering from drug refractory heart failure. However, approximately 20–30% of patients are non-responder. Cardiac magnetic resonance imaging (CMR) may play significant role in clarifying many questions in this patient population. Forty-five patients, suffering from severe drug refractory heart failure, underwent CMR before applying CRT. Left ventricular end-diastolic, end-systolic volumes, ejection fraction, myocardial mass, wall motion disturbances, localisation of non-viable myocardium were determined. Left ventricular dyssynchrony was determined by illustrating wall-time thickening in short-axis slices of left ventricle from basis to apex. CMR-proved underlying heart disease were postinfarction heart failure, dilated cardiomyopathy and non-compaction cardiomyopathy in 62, 27 and in 11%, respectively. Mean left ventricular ejection fraction was 24.5±10%, intraventricular dyssynch...

Adenosine-resistant narrow-QRS tachycardia

A 72-year-old female patient had been having two or three episodes each year of spontaneously terminated palpitations with a rapid heartbeat. She had no history of heart disease. On the day of her admission, she had an attack of tachycardia lasting over an hour and accompanied by an increasing shortness of breath. Prehospital electrocardiogram (ECG) revealed a narrow-QRS tachycardia. Carotid massage and adenosine (a 6-mg and a 12-mg iv. bolus) did not terminate the arrhythmia and the patient was referred to us for admission.