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Cardiac resynchronization therapy (CRT) is an advanced device-based intervention for patients with heart failure characterized by reduced left ventricular ejection fraction and intraventricular conduction delays, most commonly left bundle branch block. This electrical dyssynchrony leads to uncoordinated ventricular contractions, reduced stroke volume, and worsening heart failure symptoms. CRT delivers timed electrical impulses to both ventricles through specialized pacing leads, restoring synchronized contraction, enhancing cardiac output, and improving mechanical efficiency. Extensive clinical evidence demonstrates that CRT reduces mitral regurgitation, enhances functional status and quality of life, decreases hospitalizations, and improves survival in patients who are appropriately selected. As such, CRT plays a pivotal role in the treatment of advanced heart failure with dyssynchrony. This continuing education course equips clinicians with the knowledge and skills necessary to identify suitable candidates for CRT, using established clinical guidelines and diagnostic criteria. Participants learn best practices in device implantation techniques, programming, and postoperative optimization to maximize therapeutic outcomes. The course emphasizes the importance of interprofessional collaboration among cardiologists, electrophysiologists, imaging specialists, heart failure nurses, and device technicians to ensure timely referrals, accurate diagnosis, and coordinated follow-up care. This integrated team approach enhances patient outcomes by facilitating precision in treatment planning, reducing complications, and supporting long-term management strategies tailored to each patient’s needs. Objectives: Identify patients with heart failure who meet guideline-based criteria for cardiac resynchronization therapy. Screen for electrical conduction abnormalities, such as left bundle branch block, that indicate cardiac resynchronization therapy benefit. Evaluate patients for potential complications of cardiac resynchronization therapy. Collaborate with an interprofessional team to ensure optimal outcomes for patients who need cardiac resynchronization therapy. Access free multiple choice questions on this topic.

Heart failure is one of the major causes of morbidity and mortality worldwide, and it is associated with poor life expectancy, poor quality of life, and a higher economic burden on the healthcare system.[1] Heart failure can result from several causes, but left ventricular (LV) systolic dysfunction is the major cause of heart failure. Over the past 3 decades, advances in the medical management of heart failure cases with reduced ejection fraction (EF) have improved patient survival. Still, the morbidity and mortality related to heart failure have remained elevated.[2] With an increase in the population's age and advances in treating ischemic heart diseases, the number of patients with heart failure continues to grow, introducing significant challenges to managing cardiac arrhythmia and advanced heart failure.[3] In patients with heart failure with reduced EF, electromechanical dyssynchrony from intraventricular conduction delays leads to hemodynamic inefficiencies, which consequently worsen functional mitral regurgitation and LV remodeling, eventually leading to poor outcomes.[4][5] In the early 1990s, it was identified that electromechanical dyssynchrony plays a prominent role in heart failure. Pacing devices that stimulate multiple areas of the heart simultaneously could be used to offset this dyssynchrony and conduction delay.[6] In the late 1990s, Auricchio and Kass first described the efficacy of multisite pacing in humans, which led to the development of cardiac resynchronization therapy (CRT), the first use of artificial electrical stimulation for treating heart failure.[7] Since then, CRT has been an important treatment modality for those with heart failure with reduced EF.[8] This review examines the use of implantable pacing devices in heart failure, with a primary focus on biventricular pacing (cardiac resynchronization). Also discussed are the pathophysiology, indications, complications, and clinical significance.

Major complications associated with CRT device implantation include the following: Access site bleeding and pocket hematoma The incidence in clinical trials is reported up to 2.5%.[35] However, in routine clinical practice, the incidence of pocket hematomas may be higher than this, as the trials only reported those hematomas requiring intervention. Pocket hematoma and early reintervention for pocket hematoma are associated with an increased incidence of device infection. Lead dislodgement Results from CRT trials demonstrated a rate of lead dislodgement from 2.9% to 10%. The incidence of LV lead dislodgement is higher than that of the RA and RV leads.[36] Infection This is one of the challenging complications related to CRT and other cardiac implantable devices. The incidence of device-related infection for CRT implantation is reported to be up to 3.3%. Male sex, prior device-related infection, and reimplantation are reported to have a higher incidence of device-related infections.[37] Pneumothorax This is a rare complication, reported in up to 0.66% of cardiac pacing device implantations. Subclavian access, chronic obstructive pulmonary disease, and advanced age (eg, 80 and older) at implantation are reported with a higher pneumothorax incidence. The cephalic vein cut-down technique should be used whenever possible to avoid this complication.[38] Coronary sinus perforation/dissection Coronary venous dissection is a rare but recognized complication of LV lead placement during the implantation of a CRT device. This complication occurs in up to 0.28% of cases and is reported to prolong postprocedural hospital stays.[38] Other complications may include cardiac tamponade, myocardial injury, lead fracture, pocket erosion, and phrenic nerve stimulation. Inappropriate phrenic nerve stimulation occurs in up to 13% of patients undergoing LV lead placement and is more common at midlateral, midposterior, and apical sites.[39]

Effectively delivering CRT relies on the combined skills, strategies, and coordinated efforts of a multidisciplinary team. Advanced clinicians must accurately identify appropriate candidates, balancing clinical criteria such as reduced ejection fraction and conduction delays with individualized risk-benefit considerations. Electrophysiologists bring specialized procedural skills in lead placement and device programming, while nurses play a crucial role in patient education, perioperative care, and ongoing symptom monitoring. Pharmacists contribute by optimizing medication regimens to complement device therapy, managing heart failure pharmacotherapy, and minimizing drug-device interactions. Dietitians and rehabilitation specialists further enhance outcomes by supporting lifestyle modifications and cardiac rehabilitation efforts tailored to each patient’s needs. Interprofessional communication and seamless care coordination are crucial for maximizing CRT benefits and ensuring patient safety. Regular multidisciplinary meetings, structured handoffs, and shared electronic health records facilitate clear communication of clinical goals, device settings, and patient progress. Collaborative, interdisciplinary efforts support the timely identification of nonresponders, early management of complications, and individualized adjustments to care plans. Coordination minimizes errors, reduces delays, and enhances patient safety, ultimately leading to improved outcomes and patient-centered care that prioritizes the well-being and satisfaction of patients undergoing CRT.