Abstract | December 19, 2022
Acute Cardiac Findings After an Episode of Shortness of Breath: An Unusual Presentation
Learning Objectives
- Illustrates the prompt and accurate diagnosis of bradycardia and heart block causing shortness of breath, allowing the patient to receive a pacemaker in a timely fashion.
- The importance of knowing off-label use and side effects of medication, and the benefits of inter-professional management in patients.
Introduction: Dyspnea is a common symptom that affects many patients and is frequently associated with pulmonary processes. However, dyspnea may be a manifestation secondary to a cardiac or hematologic cause. By recognizing what is causing shortness of breath, prompt emergency medical care can be provided.
Case Presentation: I present a case of a 77-year-old male with a past medical history of COPD with CPAP at night, congestive heart failure, angina on ranolazine, bradycardia on theophylline, DVT, and PE, who presents with shortness of breath. His symptoms woke him this morning and continued. He endorses chest pain, worse with deep inspiration.
Upon arrival, his temperature was 97.8 F, pulse 42, respiratory rate 22, oxygen saturation of 96% on 3L nasal cannula, and a blood pressure of 102/52. He did not appear to be in distress. Physical exam was notable for bradycardia and clear lungs.
His labs and chest x-ray were unremarkable. EKG demonstrated a significantly prolonged PR interval with a rate of 42, whereas past EKGs demonstrated a heart rate between 80-110 beats per minute with normal PR intervals.
The patient endorsed that he has a history of bradycardia and takes theophylline. Pharmacy was consulted and they confirmed that theophylline can be used off-label to improve bradycardia. However, research shows that when compared to rate-response pacemaker vs theophylline, patients with a pacemaker had a significantly lower incidence of syncope.1 Additionally, ranolazine has been linked to bradycardia, but review of the 5 major ranolazine trials, demonstrated that less than 2% of patients experienced this side effect. 2
Given that the patient continued to be bradycardic with prolonged PR intervals, a repeat EKG was completed, demonstrating a low junctional rhythm with a Mobitz type two heart block. He then went into complete heart block with worsening PR intervals. Cardiology was consulted and recommended that the patient be admitted for placement of a temporary pacemaker for symptomatic bradycardia and complete heart block.
The patient was admitted, received a pacemaker, and appropriately paced at 92 beats per minute. He will follow up with cardiology in 2 weeks and sooner if needed.
References:
- Homoud, Munther K. “Sinus Node Dysfunction: Treatment.” Up To Date, 28 June 2021, https://www-uptodate-com.rosalindfranklin.idm.oclc.org/contents/sinus-node-dysfunction-treatment?search=theophylline+bradycardia&source=search_result&selectedTitle=1~150&usage_type=default&display_rank=1.
- Zaidi, Syed Arsalan Akhter, et al. “Ranolazine Induced Bradycardia, Renal Failure, and Hyperkalemia: A Brash Syndrome Variant.” Case Reports in Medicine, Hindawi, 31 Dec. 2019, https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6955118/.
