[Malignant bileaflet mitral valve prolapse syndrome in otherwise idiopathic ventricular fibrillation]. / Malignes Mitralklappenprolapssyndrom bei "idiopathischem" Kammerflimmern.

A 32-year-old, otherwise healthy woman was admitted after successful out-of-hospital resuscitation due to ventricular fibrillation. Established cardiac, pulmonary, metabolic, and toxicological causes were excluded. However, persisting (biphasic) negative T waves in the inferior ECG leads and premature ventricular contractions (PVC) were noted. PVC morphology indicated a focus alternating between the posterior papillary muscle/the left posterior fascicle and the left ventricular outflow tract region/anterior papillary muscle. Echocardiography revealed a bileaflet mitral prolapse with mild mitral valve regurgitation. This case is a typical presentation of the recently described malignant bileaflet mitral valve prolapse syndrome. The patient was discharged without overt neurological deficit after implantation of a cardioverter-defibrillator.

Pulmonary vein anatomy predicts freedom from atrial fibrillation using remote magnetic navigation for circumferential pulmonary vein ablation.

AIMS: Multidetector computed tomography (MDCT) is frequently used to guide circumferential pulmonary vein ablation (PVA) for treatment of atrial fibrillation (AF) as it offers accurate visualization of the left atrial (LA) and pulmonary vein (PV) anatomy. This study aimed to identify if PV anatomy is associated with outcomes following PVA using remote magnetic navigation (RMN). METHODS AND RESULTS: We analysed data from 138 consecutive patients and 146 ablation procedures referred for PVA due to drug-refractory symptomatic AF (age 63 ± 11 years; 57% men; 69% paroxysmal AF). The RMN using the stereotaxis system and open-irrigated 3.5 mm ablation catheters was used in all procedures. Prior to PVA, all patients underwent electrocardiogram-gated 64-MDCT for assessment of LA dimensions, PV anatomy, and electro-anatomical image integration during the procedure. Regular PV anatomy was found in 68%, a common left PV ostium was detected in 26%, and variant anatomy of the right PVs was detected in 6%. After a mean follow-up of 337 ± 102 days, 63% of the patients maintained sinus rhythm after the initial ablation, and 83% when including repeat PVA. Although acutely successful PV isolation did not differ between anatomical subgroups (regular 3.5 ± 0.8 vs. variant 3.2 ± 1.3; P = 0.31), AF recurrence was significantly higher in patients with non-regular PV anatomy (P = 0.04, hazard ratio 1.72). Pulmonary vein anatomy did not influence complication rates. CONCLUSION: Pulmonary vein anatomy assessed by MDCT is a good predictor of AF recurrence after PVA using RMN.

Accuracy of 64-multidetector computed tomography coronary angiography in patients with symptomatic atrial fibrillation prior to pulmonary vein isolation.

AIMS: Aim of our study was to investigate the value of multidetector computed tomography (MDCT) for detecting significant stenoses of coronary arteries in patients with symptomatic atrial fibrillation (AF) prior to pulmonary vein (PV) ablation (PVA). BACKGROUND: Many patients undergoing PVA for AF receive three-dimensional computed tomography or magnetic resonance tomography imaging for improving anatomical orientation. METHODS: One-hundred and eighty-one patients with AF refractory to antiarrhythmic treatment underwent ECG-gated 64-MDCT for identification of PV anatomy and simultaneous assessment of coronary vessels before PVA. No additional radiation was incurred for MDCT coronary angiography during MDCT scan. Pretest probability for obstructive coronary artery disease (CAD) was estimated. Invasive coronary angiography (ICA) was performed in all patients with at least intermediate risk of CAD. RESULTS: Eighty-six out of 181 patients (48%) had ICA and MDCT, 95 patients (52%) underwent MDCT alone. ICA revealed significant stenoses in 9% of the catheterized patients (8/86). MDCT investigation lead to a sensitivity of 90% (9/10), specificity of 98% (829/844 lesions), positive predictive value (PPV) of 39% (9/24), and negative predictive value (NPV) of 100% (829/830 lesions) for the detection of >50% stenoses seen on ICA. All patients with a significant stenosis were classified as patients with CAD. Overall prevalence of significant CAD detected by MDCT was found to be low with 10% of patients and 2% of all segments. CONCLUSION: MDCT coronary angiography is sensitive and highly specific in patients presenting for PVA. In this group a negative scan reliably excludes significant CAD. These data suggest that MDCT coronary angiography can replace ICA prior to PVA.

Remote magnetic catheter navigation for cavotricuspid isthmus ablation in patients with common-type atrial flutter.

BACKGROUND: Conventional catheter ablation of cavotricuspid isthmus (CTI)-dependent atrial flutter is a widely applied standard therapy. Remote magnetic catheter navigation (RMN) may provide benefits for different ablation procedures, but its efficacy for CTI ablation has not been evaluated in a randomized, controlled trial. METHODS AND RESULTS: Ninety patients undergoing de novo ablation of atrial flutter were randomly assigned to conventional manual (n=45) or RMN-guided (n=45) CTI ablation with an 8-mm-tip catheter. Complete bidirectional isthmus block was achieved in 84% (RMN) and 91% (conventional catheter ablation) of the cases (P=0.52). RMN was associated with shorter fluoroscopy time (median, 10.6 minutes; interquartile range [IQR], 7.6 to 19.9, versus 15.0 minutes; IQR, 11.5 to 23.1; P=0.043) but longer total radiofrequency application (17.1 minutes; IQR, 8.6 to 25, versus 7.5 minutes; IQR, 3.6 to 10.9; P<0.0001), ablation time (55 minutes; IQR, 28 to 76, versus 17 minutes; IQR, 7 to 31; P<0.0001), and procedure duration (114+/-35 versus 77+/-24 minutes, P<0.0001). Procedure duration in the RMN group did not decrease significantly with case experience. Long-term procedure success, defined as achievement of complete CTI block and freedom from atrial flutter recurrence during 6 months of follow-up, was lower in the RMN group (73% versus 89%, P=0.063). Right atrial angiography after ablation revealed no significant differences between groups in terms of right atrial diameter or CTI length, morphology, and angulation. Furthermore, none of these parameters was predictive for difficult (ablation time >20 minutes) or unsuccessful ablation. CONCLUSIONS: RMN-guided CTI ablation is associated with reduced radiation exposure but prolonged ablation and procedure times as compared with conventional catheter navigation. Our findings suggest that ablation lesions produced with an RMN-guided 8-mm catheter are less effective irrespective of CTI anatomy. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT00560872.

Differential effects of theophylline on sympathetic excitation, hemodynamics, and breathing in congestive heart failure.

BACKGROUND: Patients with heart failure have high levels of central sympathetic outflow and also have a high prevalence of sleep-related breathing disorders, predominantly central sleep apnea. The options for treating central sleep apnea in heart failure are limited and include theophylline. Whether theophylline alters sympathetic activity in heart failure patients is not known. METHODS AND RESULTS: Using a single-blinded, randomized, placebo-controlled study design, we investigated the sympathetic, hemodynamic, neurohumoral, and ventilatory effects of theophylline in patients with congestive heart failure compared with healthy control subjects closely matched for age, sex, and body mass index. Theophylline increased muscle sympathetic nerve activity and lowered transcutaneous CO2 in the control subjects but only lowered transcutaneous CO2 in the heart failure patients. Theophylline nearly doubled plasma renin concentration in both the healthy subjects (P<0.01) and the heart failure patients (P<0.02). CONCLUSIONS: Our study shows that in heart failure patients, there are differential effects of theophylline: in contrast to healthy subjects, theophylline does not increase sympathetic activity in heart failure, whereas increases in plasma renin and ventilation are still evident. These novel findings may have important implications for understanding the potential harmful and beneficial effects of theophylline and related substances in heart failure patients.