Heart flutters may weaken lungs and muscles, new study suggests

Copied word for word from the study's registry entry, so the wording is the study team's rather than ours.

Inclusion Criteria for Individuals with Premature Ventricular Complexes (PVCs): * Aged between 18 and 80 years * Presence of symptomatic premature ventricular complexes resistant to ≥1 antiarrhythmic medication (including β-blockers and calcium channel blockers) * Premature ventricular complex burden ≥10% * Ventricular arrhythmias originating from any focus within the right or left ventricle * Physically able to participate in all study assessments * Willingness to participate in the study by providing written informed consent Inclusion Criteria for Control Group Participants: * Aged between 18 and 80 years * Healthy individuals * Willingness to participate in the study * Physically able to participate in all study assessments Exclusion Criteria for Individuals with Premature Ventricular Complexes (PVCs): * Left ventricular ejection fraction (LVEF) \<45% unless PVC-induced cardiomyopathy is documented (defined as a \>15% improvement in LVEF following reduction of PVC burden through pharmacological therapy or ablation) * Progressive decline in LVEF within the last 4 months, regardless of etiology * Severe heart failure classified as New York Heart Association (NYHA) Class ≥III * Ventricular arrhythmias attributed to underlying structural heart disease, known myocardial scar, or myocarditis * Change in the dosage of antiarrhythmic medications (including β-blockers and calcium channel blockers) within 2 months prior to enrollment * Failed catheter ablation within 3 months prior to enrollment * Known thyroid disorders or individuals undergoing renal dialysis * Life expectancy \<12 months * Presence of angina pectoris * Diagnosis of chronic obstructive pulmonary disease (COPD) or asthma * Resting heart rate \>120 beats/min * Resting systolic blood pressure ≥180 mmHg * Resting diastolic blood pressure ≥100 mmHg * Resting peripheral oxygen saturation ≤90% Exclusion Criteria for Control Group Participants: * Presence of premature ventricular complexes * Presence of any acute or chronic medical condition