The Sports Cardiology Team: Personalizing Athlete Care Through a Comprehensive, Multidisciplinary Approach.

Objective: To systematically investigate and document the infrastructure, practices, recommendations, and clinical consequences of a structured, organized sports cardiology multidisciplinary team (MDT) for athletes and patients who wish to engage in sports and exercise. Patients and Methods: We established bimonthly sports cardiology MDT meetings, with a permanent panel of experts in sports cardiology, genetics, pediatric cardiology, cardiovascular imaging, electrophysiology, and sports and exercise medicine. Cases were referred nationally or internationally by cardiologists/sports physicians. We retrospectively analyzed all MDT cases (April 10, 2019 through May 13, 2020) and collected clinical follow-up data up to 1 year after the initial review. Results: A total of 115 athletes underwent MDT review; of them, 11% were women, 65% were recreational athletes, and 54% were performing "mixed" type of sports; the mean age was 32±16 years. An MDT review led to a diagnosis revision of "suspected cardiac pathology" to "no cardiac pathology" in 38% of the athletes and increased the number of definitive diagnoses (from 77 to 109; P=.03). We observed fewer "total sports restrictions" (from 6 to 0; P=.04) and more tailored sports advice concerning "no peak load/specific maximum load" (from 10 to 26; P=.02). At the 14±6-month follow-up, 112 (97%) athletes reported no cardiovascular events, 111 (97%) athletes reported no (new) cardiac symptoms, 113 (98%) athletes reported adherence to the MDT sports advice, and no diagnoses were revised. Conclusion: Our experiences with a comprehensive sports cardiology MDT demonstrate that this approach leads to higher percentages of definitive diagnoses and fewer cardiac pathology diagnoses, more tailored sports advice with excellent rates of adherence, and fewer total sports restrictions. Our findings highlight the added value of sports cardiology MDTs for patient and athlete care.

Flecainide therapy reduces exercise-induced ventricular arrhythmias in patients with catecholaminergic polymorphic ventricular tachycardia.

OBJECTIVES: This study evaluated the efficacy and safety of flecainide in addition to conventional drug therapy in patients with catecholaminergic polymorphic ventricular tachycardia (CPVT). BACKGROUND: CPVT is an inherited arrhythmia syndrome caused by gene mutations that destabilize cardiac ryanodine receptor Ca(2+) release channels. Sudden cardiac death is incompletely prevented by conventional drug therapy with ß-blockers with or without Ca(2+) channel blockers. The antiarrhythmic agent flecainide directly targets the molecular defect in CPVT by inhibiting premature Ca(2+) release and triggered beats in vitro. METHODS: We collected data from every consecutive genotype-positive CPVT patient started on flecainide at 8 international centers before December 2009. The primary outcome measure was the reduction of ventricular arrhythmias during exercise testing. RESULTS: Thirty-three patients received flecainide because of exercise-induced ventricular arrhythmias despite conventional (for different reasons, not always optimal) therapy (median age 25 years; range 7 to 68 years; 73% female). Exercise tests comparing flecainide in addition to conventional therapy with conventional therapy alone were available for 29 patients. Twenty-two patients (76%) had either partial (n = 8) or complete (n = 14) suppression of exercise-induced ventricular arrhythmias with flecainide (p < 0.001). No patient experienced worsening of exercise-induced ventricular arrhythmias. The median daily flecainide dose in responders was 150 mg (range 100 to 300 mg). During a median follow-up of 20 months (range 12 to 40 months), 1 patient experienced implantable cardioverter-defibrillator shocks for polymorphic ventricular arrhythmias, which were associated with a low serum flecainide level. In 1 patient, flecainide successfully suppressed exercise-induced ventricular arrhythmias for 29 years. CONCLUSIONS: Flecainide reduced exercise-induced ventricular arrhythmias in patients with CPVT not controlled by conventional drug therapy.

Clinical results of far-field R-wave reduction with a short tip-ring electrode.

BACKGROUND: Far-field R-wave (FFRW) sensing of the atrial lead of AAI or DDD pacemakers causes incorrect mode switches and remains a problem in patients with atrial arrhythmias in whom low voltage sensing is essential. We studied a pacing electrode with a short tip-ring distance (1.1 mm). We compared our findings with recordings from a conventional electrode with a larger tip-ring distance (10 mm). METHODS: Thirty-six consecutive patients with an indication for DDD pacing were implanted with the short tip-ring electrode. Another 23 patients received the conventional electrode. FFRW and P-wave amplitudes during pacing and intrinsic ventricular depolarization were measured at implantation. Measurements were repeated before hospital discharge and at follow-up between 10 and 14 days after implantation. RESULTS: P-wave amplitude was slightly smaller in the short tip-ring group (2.71+/-1.04 vs 3.17+/-1.30 mV in the conventional group, respectively, P=NS). All P-waves exceeded 1.2 mV. FFRW during pacing was 0.07+/-0.05 in the short tip-ring group and 0.54+/-0.32 mV in the conventional group (P<0.001). FFRW during intrinsic rhythm was 0.08+/-0.04 and 0.55+/-0.31 mV, respectively (P<0.001). The ratio between P-wave and FFRW was 48.6+/-27.2 in the short tip-ring group and 7.3+/-4.4 in the conventional group (P<0.001). FFRW and P-wave amplitudes did not change at hospital discharge or during follow-up. CONCLUSION: FFRW can be suppressed without compromising P-wave sensing by using a pacing electrode with a short tip-ring distance. Whether reduced FFRW amplitude results in clinical endpoints remains to be determined.

Far-field R-wave reduction with a novel lead design: experimental and human results.

INTRODUCTION: The purpose of this study was to examine a bipolar screw-in lead (NL), specially designed to reduce unwanted far-field R-wave (FFRW) signal detection in an acute human setting. The results were compared with animal experiments. METHODS: The newly designed lead with a center-to-center distance between the anode and cathode electrodes of 3.23 mm, corresponding to an inter-electrode spacing of 1.1 mm was implanted in nine canines with a follow-up of 6 months. Sensing of P waves, FFRW signals, pacing threshold, and impedance was measured at regular intervals. As a result of the positive outcome with the animal study, an acute human experiment was performed. In patients scheduled for conventional dual chamber pacemaker implantation, the NL was compared to a Tendril Model 1388T bipolar screw-in lead (St. Jude Medical, CRMD, Sylmar, CA). RESULTS: Utilizing a tip-to-ring distance of 1.1 mm, the optimum P wave to FFRW ratio was found in animal experiments. In the acute human tests in 15 patients, the mean P-wave voltage of the 1388T lead of 3.30 +/- 1.54 mV was slightly larger than that of the NL, at 2.55 +/- 1.11 mV, but did not differ significantly (P = 0.13). The FFRW voltage of the 1388T lead was 0.62 +/- 0.37 mV and was significantly greater from that of the NL, at 0.10 +/- 0.08 mV (P < 0.0001). Pacing thresholds and pacing impedances were comparable. CONCLUSION: Animal testing results were reproducible in the acute human test setting. The lead reduced the paced FFRW signal amplitudes significantly, allowing for high atrial sensitivity settings but without sensing the FFRW. A robust P-wave signal could be retained.