Samuel Hong, MD
UCLA David Geffen School of Medicine/UCLA Medical Center Program
Los Angeles, California
Disclosure information not submitted.
Title: Massive Pulmonary Embolism Presenting as Complete Heart Block under Monitored Anesthesia Care
Case Report Body:
Introduction:
Pulmonary emboli (PE) can present with a variety of hemodynamic and laboratory abnormalities. Rarely, they can present as significant brady-arrhythmias, including complete heart block (CHB). In this case, we describe a case of massive pulmonary embolism resulting in CHB in a sedated patient.
Description:
A 47 year-old woman with end-stage renal disease on hemodialysis due to diabetes presented for outpatient upper extremity angiogram and thrombectomy for a thrombosed arteriovenous fistula. She had a history of coronary artery disease and mild ischemic cardiomyopathy with a left ventricular ejection fraction of 47%. Monitored anesthesia care was initiated with a propofol infusion without incident. Immediately after the surgical team introduced the vascular access needle and wire, the patient was noted to have labored breathing. At the same time, continuous EKG monitoring revealed CHB with a junctional escape rhythm in the 30s. Pulse was not palpable, and a code was called for PEA arrest. She was emergently intubated and after 2 rounds of CPR and epinephrine, ROSC was achieved. Bedside TTE revealed dilated and dysfunctional right ventricle, with RVSP >60 and an underfilled LV. A femoral venous sheath was placed in case transvenous pacing was required. However, the CHB was transient in nature and converted to sinus tachycardia after the first dose of epinephrine. The patient was started on epinephrine and heparin infusions and transferred to the ICU. CT pulmonary angiogram revealed massive PE. The following day, she underwent catheter-directed thrombolysis and was weaned off epinephrine with an intact neurologic status. She had no recurrence of CHB.
Discussion:
While arrythmias related to pulmonary emboli are relatively common, the presentation of complete heart block is rare. There are few reported cases of transient complete heart block as a complication of pulmonary embolism. Moreover, this patient did not have prior conduction abnormalities. The mechanism for this phenomenon is not well understood, but could include ischemia, RV strain, and an abrupt increase in vagal tone. The simultaneous presentation of PE and CHB can be challenging. This case illustrates the importance of considering PE as an etiology of CHB before concluding that it is due to a primary conduction abnormality.