Coronary fibromuscular dysplasia with three-vessel involvement: a rare cause of ischaemic dilated cardiomyopathy in a very young male.

Coronary artery disease of non-atherosclerotic aetiology, while rare in incidence, can have a wide aetiology, such as fibromuscular dysplasia, which is a non-inflammatory arteriopathy of numerous histopathological types of fibromuscular tissue accumulation. This brief report describes the case of a 22-year-old male with a recently developed dilated cardiomyopathy and a history of aborted cardiac arrest at the age of 14 years. Coronary angiogram revealed severe three vessels disease, while optical coherence tomography established fibromuscular dysplasia as aetiology. Balloon and stent angioplasty was performed guided by fractional flow reserve with acceptable angiographic result.

Changes in left atrial size and function early after cardiac resynchronization therapy as assessed by conventional two-dimensional echocardiography.

AIMS: Cardiac resynchronization therapy (CRT) was shown to improve left atrial (LA) size and function within months after the procedure. We aimed to assess the impact of CRT on left atrial (LA) size and function within days after the procedure. Materials and methods: Twenty-eight consecutive patients with CRT were evaluated before the procedure and within 3 days afterwards, and 25 of them were also examined at three months. Echocardiography was performed to assess LA size and function: LA volumes indexed to body surface (LAVIs) were measured at different moments during the cardiac cycle: ventricular end-systole - maximum LAVI (LAVImax), before atrial systole (LAVIpreA), and at ventricular end-diastole - minimum LAVI (LAVImin). These measurements were further used to calculate LA function parameters: LA total emptying fraction, activeemptying fraction and passive emptying fraction. RESULTS: LAVImax decreased within days after the procedure - 45.5 mL/ m2 (38.2-56.7) vs. 42.9 mL/m2 (32.1- 56.2), p <0.05, as did LAVImin - 27.1 mL/m2 (22.9-41.9) vs. 25.9 mL/m2 (17.8-38.1), p <0.05, and LAVIpreA - 40.0 mL/m2 (31.3-53.0) vs. 35.5 mL/m2 (25.8-49.1), without significant changes in functional parameters. All LAVIs were correlated to the diastolic filling time/RR interval ratio after CRT, but not before. CONCLUSIONS: LAVIs may be reduced within days after the implant procedure in responders to CRT, while atrial functional parameters remain unchanged. Correlations beween LAVIs and the diastolic filling time/RR interval ratio after CRT suggest that early optimization of atrio-ventricular and ventriculo-ventricular delays may have a positive and immediate impact on LA size.

Echocardiographic evaluation of mechanical dyssynchrony in heart failure patients with reduced ejection fraction.

The aim of this study is to observe the differences between mechanical and electrical dyssynchrony in patients with impaired systolic ventricular function and symptomatic heart failure and to highlight the importance of mechanical dyssynchrony besides electrical dyssynchrony in clinical guidelines and clinical practice. Fifty-eight patients with heart failure, who are with the New York Heart Association (NYHA) functional class II-IV and left ventricular ejection fraction (LVEF) under 35%, were enrolled. Patients were divided into two groups, according to the duration of QRS complex (> 120 ms and ≤ 120 ms respectively). Echocardiographic parameters of interventricular (interventricular mechanical delay - IMD) and intraventricular (septal-to-posterior wall motion delay - SPWMD) dyssynchrony were measured in both groups. Results indicate that the duration of the QRS complex (i.e. electrical dyssynchrony) is not a fully reliable indicator of ventricular dyssynchrony; therefore ecocardiographic evaluation of mechanical dyssynchrony should also be recommended for better selection of candidates for cardiac resynchronization therapy (CRT).

Intraprocedural predictors of successful ablation of slow pathway for atrioventricular nodal reentrant tachycardia.

Atrioventricular nodal reentrant tachycardia (AVNRT) is one of the most common causes of paroxysmal supraventricular tachycardia. For many years, the pharmacological approach was the only therapeutic modality available for managing this arrhythmia. More recently transcatheter radiofrequency (RF) ablation has become a safe and effective alternative to medical therapy. During the last 2 years, 20 patients with AVNRT were evaluated in our department. The diagnosis was made using the classical electrophysiological protocols with three multipolar catheters placed in AV node-His region, coronary sinus and a mapping/ablation catheter. In all cases, a discontinuous AV conduction curve during programmed atrial stimulation with progressively increasing prematurity was demonstrated associated with AV nodal echo beats and induction of the arrhythmia. Typical AVNRT was present in 19 patients. One patient with typical AVNRT also had inducible unusual (slow-slow) AVNRT. An additional patient had unusual slow-slow variant of AVNRT. The arrhythmia was treated in all cases by RFA of the slow AV node pathway, guided by anatomic and electrophysiologic criteria. RF ablation was successful in all patients. Two patients had clinical recurrence of arrhythmia; all have undergone successful reablation. No patient had significant complications of the procedure. As intraprocedural predictors for successful RF ablation were considered the slow pathway potentials with evidence of the junctional accelerated rhythm during RF current delivery and modification of AV node physiology with noninducibility of arrhythmia after RF ablation. The persistence of slow pathway with or without single AV node echo beat during a limited numbers of atrial extrastimuli was accepted as a successful procedure. In all cases, the AV node physiology was tested also after autonomic modulation of AV node. In both cases with clinical recurrence, the intraprocedural RF ablation results were misevaluated probably because of the autonomic modulation of fast pathway electrophysiology masking the persistence of slows pathway conduction. In conclusion invasive electrophysiological evaluation and RF ablation not only eliminate AVNRT, but also provide a unique opportunity to gain insights into the complexity of AV node physiology. This complexity makes more difficult the evaluation of the success of slow pathway ablation for AVNRT and a careful examination of multiple criteria is necessary for a good procedural result.