Left bundle branch area pacing - restoring the natural order: A Case Report.

INTRODUCTION: Recent studies have shown that His-bundle pacing could be an alternative in patients requiring cardiac resynchronization therapy as it is comparable or better in terms of amelioration of ventricular activation, narrowing of the QRS complex, or clinical outcomes. However, in case of high threshold at the level of His-bundle or inability to correct conduction through a diseased His-Purkinje system other option should be searched like left bundle pacing. PATIENT CONCERNS: A 77-year-old man presented to the Emergency Department for dizziness and dizziness and lightheadedness due to an intermittent 2:1 atrioventricular block with a QRS complex morphology of a major left branch block. DIAGNOSIS: Given the documented symptomatic 2:1 AV block, according to the European Guideliness the patient was considered to have a class 1 indication of permanent double chamber cardiostimulation. INTERVENTIONS: A lead delivery system with a C315 His catheter and a Select Secure 3830 69 cm pacing lead were placed at the His bundle area with important narrowing of the QRS complex but with an unacceptable high threshold. The delivery system was moved towards the apex 1,5 cm and the lead screwed deep into the septum until capture of the left bundle branch was achieved with complete normalization of the conduction troubles. OUTCOMES: At 3 month follow-up the patient was asymptomatic and the pacing and sensing thresholds remained at same values as during implantation: 0.75/0.4 ms and 14 mV respectively. CONCLUSION: Left bundle-pacing represents the next step of His-Purkinje system pacing to overcome all difficulties related to His-bundle pacing.

His bundle pacing - a curative method: A Case Report.

INTRODUCTION: Pacing of the His bundle and conduction system seems an attractive site for pacing. Lead placement in His-pacing might be technically challenging due to surrounding structures and particular anatomic location. PATIENT CONCERNS: A 62-years old male patient was admitted for recurrent syncope. Electrocardiographic monitoring revealed periods of complete atrioventricular block with left branch block morphology and a QRS duration of 160 ms. DIAGNOSIS: A diagnosis of intermittent complete atrioventricular block was made with a Class I indication of permanent dual-chamber cardiac pacing. INTERVENTIONS: A lead delivery system with a C315 His catheter and a Select Secure 3830 69 cm pacing lead was placed at the septal area of the atrioventricular junction with good pacing and sensing thresholds. An important narowing of the QRS was observed. OUTCOMES: After the procedure, good pacing and sensing parameters were observed.Echocardiography revealed disappearance of the previously recorded ventricular dyssynchronism.Device follow-up at 1 month and 3 months showed stable pacing and sensing parameters. CONCLUSION: Pacing the distal His bundle normalized the QRS complex, therefore "curing" both the atrioventricular and the left bundle branch conduction abnormalities. As such, the technique can be used as an alternative to cardiac electrical resynchronization therapy with acceptable pacing and detection thresholds and better ventricular activation pattern.

Tachycardia-induced cardiomyopathy in a patient with left-sided accessory pathway and left bundle branch block: A case report.

RATIONALE: Tachycardia-induced cardiomyopathy (TIC) is defined as systolic and/or diastolic dysfunction of the left ventricle resulting from prolonged elevated heart rates, completely reversible upon control of the arrhythmia. Atrioventricular reentrant tachycardia (AVRT) is one of the most frequent causes of TIC. In its incessant form, it is unlikely to be controlled by pharmacological treatment, catheter ablation being the principal therapeutic option. The coexistence of left bundle branch block (LBBB) in patients with AVRT may cause difficulties in the early diagnosis and management of tachycardia because of the wide complex morphology, making it harder to localize the accessory pathway (AP). PATIENT CONCERNS: A 60-year-old woman, presented incessant episodes of palpitations and shortness of breath due to a LBBB tachycardia leading to hemodynamic instability. DIAGNOSIS: The patient had a wide QRS tachycardia, with LBBB morphology and a heart rate of 160/minute. Echocardiography showed global hypokinesia with 25% left ventricular ejection fraction (LVEF). Considering the patient's clinical picture, TIC was suspected. INTERVENTIONS: The electrophysiological study revealed a left lateral accessory pathway. Catheter ablation was successfully performed at the level of the lateral mitral ring. OUTCOMES: One week after the ablation the patient had no signs of heart failure and the LVEF normalized to 55%. During 6-months follow-up the patient presented no more episodes of tachycardia or heart failure and the LVEF remained normal. LESSONS: AVRT is rarely associated with intrinsic LBBB, being a potential cause of TIC. In these patients, it is unlikely to control the arrhythmia pharmacologically, catheter ablation being the best therapeutic option. The variation of QRS complex duration between LBBB pattern in SR and AVRT could be useful for early diagnosis of an ipsilateral AP on surface ECG.