Real-time cardiovascular magnetic resonance-guided radiofrequency ablation: A comprehensive review.

Cardiac magnetic resonance (CMR) imaging could enable major advantages when guiding in real-time cardiac electrophysiology procedures offering high-resolution anatomy, arrhythmia substrate, and ablation lesion visualization in the absence of ionizing radiation. Over the last decade, technologies and platforms for performing electrophysiology procedures in a CMR environment have been developed. However, performing procedures outside the conventional fluoroscopic laboratory posed technical, practical and safety concerns. The development of magnetic resonance imaging compatible ablation systems, the recording of high-quality electrograms despite significant electromagnetic interference and reliable methods for catheter visualization and lesion assessment are the main limiting factors. The first human reports, in order to establish a procedural workflow, have rationally focused on the relatively simple typical atrial flutter ablation and have shown that CMR-guided cavotricuspid isthmus ablation represents a valid alternative to conventional ablation. Potential expansion to other more complex arrhythmias, especially ventricular tachycardia and atrial fibrillation, would be of essential impact, taking into consideration the widespread use of substrate-based strategies. Importantly, all limitations need to be solved before application of CMR-guided ablation in a broad clinical setting.

A patient with ventricular tachycardia due to a novel mutation of the lamin A/C gene: case presentation and mini review.

Lamin A/C is a major constituent of the nuclear lamina, the proteinaceous meshwork underlying the inner nuclear membrane. Laminopathies are a group of diseases with heterogeneous clinical presentation. Lamin A/C mutations are a well-established cause of dilated cardiomyopathy. In our case, a novel mutation of lamin A/C presented in the typical form of cardiolaminopathy with ventricular tachycardia and mild myocardial dysfunction in an apparently healthy, middle-aged individual.

Differential vasoactive response to endothelin receptor antagonists and prostacyclin in patients with severe pulmonary hypertension.

Pulmonary hypertension (PH) is a rare disease of the pulmonary vasculature with diverse pathogenetic mechanisms. Vasoactive substances such as endothelin A receptor (ET(A)) antagonists and prostanoids have been used to improve haemodynamics and clinical outcome. We compared the hemodynamic response to BQ-123 (an ET(A) receptor antagonist) and prostacyclin or its analogue iloprost in ten patients (four men) with a mean age of 35.9+/-15.6 years. Seven patients had primary PH and three had PH owing to connective tissue disease. Patients underwent haemodynamic evaluation before and after administration of intra-atrial BQ-123 (200 mmol/min for 60 min), intravenous prostacyclin (3 ng x kg(-1) x min(-1) for 4 h) or iloprost as an aerosol (100 microg over 24 h). Response to vasodilator administration was defined as >15% decrease in pulmonary vascular resistance index (PVRI). Of the ten patients, five showed a response to BQ-123 and eight responded to prostanoids. Four patients were responders and one patient was a non-responder to both agents. PVRI decreased by 16.6+/-13.4% with BQ-123, and 24.4+/-15.7% with prostanoids (not statistically significant). The aetiology of PH did not affect the response to either drug. In conclusion, response to ET(A) antagonist or prostanoid administration can be achieved in a large group of patients with severe PH, however few patients respond identically to both agents. These findings are consistent with a multifactorial mechanism involved in this disease.