Genetic Characterization of Patients With Arrhythmia-Induced Cardiomyopathy

Inclusion Criteria:

• Presence of atrial fibrillation or atrial flutter not self-limited.

• Performance of a cardiac imaging test with systolic function analysis (echocardiogram, magnetic resonance, CT scan) during the clinical course of thearrhythmia, exhibiting a left ventricular ejection fraction (LVEF) <50%. In orderfor the test to be representative, the maximum time between the performance of theimaging test and the rhythm control procedure will be 3 months, in the absence ofintervening cardiovascular events that may have caused a variation in LVEF. In theevent that the patient had a previously known LVEF <50%, the change with respect tothis attributable to tachyarrhythmia has to be ≥10%.

• Signature of informed consent.

• Ability to understand and accept participation in the study.

Exclusion Criteria:

• Refusal of informed consent.

• Legal or juridical incapacity.

• Age <18 years.

• Life expectancy less than 1 year.

• Impossibility of a follow-up of at least 6 months.

• Presence of a ventricular rate >140 beats per minute, limiting the validity ofimaging measurements.

• Presence of known factors causing systolic ventricular dysfunction:

• Prior cardiomyopathy diagnosis.

• Severe mitral or aortic valve disease.

• Non-revascularizable ischemic heart disease.

• Context of peri-resuscitation cardiopulmonary care.

• Abusive alcohol consumption, defined as >80 grams of ethanol or >7 standardalcoholic beverages per day.

• Active treatment with chemotherapeutic agents or radiation therapy to thethorax.

• Known infection with Trypanosoma cruzi, Borrellia burgdorferi or otherinfectious agent causing cardiomyopathy.