Persistent Exertional Chest Pain in a Marathon Runner: Exercise-induced, Painful, Left Bundle Branch Block Syndrome Treated With His-Bundle Pacing

Abstract

A 49-year-old woman presented with exercise-induced chest discomfort during long-distance running that was occasionally present during rest. Significant coronary artery disease was excluded and a diagnosis of “painful left bundle branch block (LBBB) syndrome” was made after correlation of LBBB aberrancy with symptoms during Holter monitoring. The patient underwent confirmatory testing consisting of rapid atrial pacing below and above 130 beats per minute, the rate cut-off for LBBB manifestation. His bundle pacing implantation was performed resulting in both non-selective and selective morphologies depending on output, both of which manifested with a painless narrow QRS regardless of rate. She was rendered completely pain free during long-distance running and remains so 6-months later. Her pain at rest, now thought to be due to severe anxiety secondary to her painful LBBB, has also subsided. Exercise-induced, painful LBBB is a rare phenomenon that manifests as chest discomfort when LBBB is present. This disease is frequently misdiagnosed as coronary angina, has limited medical treatment options, and can be disabling. HBP is an attractive treatment for this syndrome in an effort to avoid electromechanical dyssynchrony, the presumed mechanism of discomfort. This case report adds to the growing literature of painful LBBB syndrome and its effective treatment with HBP, with the added caveat that it can present with persistent symptoms at rest, in the setting of enhanced anxiety. HBP should be considered early on in the treatment of such patients.

Painful left bundle branch block syndrome successfully treated by His-bundle pacing

“…We noticed consistent response with complete resolution of chest pain in cases treated by His-bundle pacing in five reported cases in the literature. [1][2][3][4][5] Reporting this case will increase our awareness of this clinical entity and enhance our evidence about His-bundle pacing as an effective treatment modality in this condition.…”

Exercise-Induced Bundle Branch Block - an Infrequent Incidence

“…13 Recent studies have shown that His Bundle Pacing (HBP) induces significant QRS narrowing in most patients with LBBB and even normalization in patients with shorter baseline QRS duration 14 supporting the theory of functional longitudinal dissociation in the His Bundle. HBP has also been shown to effectively alleviate symptoms in exerciseinduced painful LBBB 15 which suggests a pathology in the His bundle with altered refractoriness in a rate dependent mechanism.…”

Non-ischemic Painful Intermittent Left Bundle Branch Block With Infra-Hisian Block Treated Successfully With Biventricular Pacemaker: A Case Report and Literature Review

“…LBBB results from a degeneration of the conduction system or is a reflection of myocardial pathology. Complete LBBB is characterized by a QRS duration of 120 ms or more, predominantly upright complexes with broad-slurred R waves in leads I and V6, a QS or rS complex in lead V1, and a monophasic R wave in leads I, V5, and V6 [ 2 ]. The main causes of new onset LBBB include coronary artery disease, cardiomyopathies, and hypertension [ 3 ].…”

“…The alteration of the heart rate is considered the most common cause of ILBBB, which is usually caused by phase 3 block or tachycardia-dependent block when a stimulus reaches the tissues that are still in the refractory period [ 3 , 4 ]. Exercise-induced ILBBB is a rare phenomenon that occurs in 0.1% to 1.1% of patients undergoing diagnostic EST [ 2 ]. It has been reported that the onset of ILBBB at a heart rate greater than 125 bpm is highly consistent with normal coronary arteries, but it has been noticed to occur at a slower rate of <105 bpm, like the presentation of our patient [ 5 ].…”

“…Non-ischemic painful intermittent left bundle branch block (ILBBB) is an uncommon conduction disturbance that is often a marker for cardiac disease. The prevalence of ILBBB during exercise stress tests (EST) has been found to be 0.38% by Stein et al, but other investigators suggest it could be as high as 1.1% [ 1 , 2 ]. Patients present with varying symptoms, from mild and self-limiting chest discomfort to severe, debilitating pain with exertion or even at rest.…”