Correspondence

An Unusual Complication of Support with a Continuous-Flow Cardiac Assist Device

N Engl J Med 2007; 357:936-937August 30, 2007

Article

To the Editor:

A 61-year-old man in cardiogenic shock was recently transferred to our hospital. Angiography revealed total occlusion of the left anterior descending coronary artery and an 80% ostial stenosis of the right coronary artery. Since he had persistent pulmonary hypertension, he was not considered to be a candidate for transplantation. A HeartMate II Left Ventricular Assist System (Thoratec) was implanted for permanent hemodynamic support, and bypass grafting to the right coronary artery was performed.

On postoperative day 3, echocardiography showed that the left ventricle was poorly decompressed, with paradoxical motion of the interventricular septum. The left ventricular assist device (LVAD) was adjusted to increase flow, which augmented decompression of the left ventricle, with the septum returning to midline.

On the morning of postoperative day 10, the patient's condition was stable while he received epinephrine at a dose of 0.07 μg per kilogram of body weight per minute, and the mean arterial pressure was maintained at 85 to 90 mm Hg with the LVAD at 9800 rpm. Later that afternoon, he went into atrial fibrillation, and his automatic implantable cardiac defibrillator fired five consecutive times. Late in the evening, anuria developed, and he continued to be in atrial fibrillation despite the administration of amiodarone and magnesium therapy. He had a decreasing mean arterial pressure despite treatment with epinephrine and vasopressin, and his central venous pressure was rising (up to 19 mm Hg). Echocardiography showed a dilated left ventricle with a dyskinetic septum and mild-to-moderate right ventricular hypokinesis. Hemodialysis was initiated to reduce pulmonary vascular resistance. Shortly thereafter, the patient became profoundly hypotensive, and resuscitation was attempted with fluids, epinephrine, and phenylephrine. Unfortunately, these attempts failed, and the patient died.

On postmortem examination, the LVAD was found to be intact, with no distortion of its position or outflow graft. The outflow graft was patent. Once the heart was opened, a ventricular septal defect was apparent, and its location was close to the LVAD inflow cannula (Figure 1Figure 1Intraventricular View of the Left Ventricle at Autopsy.). The shape and size of the septal defect corresponded to the shape and size of the inflow cannula. No evidence of acute myocardial infarction was found. The cause of death was determined to be an acute ventricular septal defect caused by erosion of the LVAD's inflow cannula into the septum.

This is a very unusual case of the formation of a ventricular septal defect, apparently secondary to erosion from the inflow cannula of an LVAD into the interventricular septum. This is a potentially fatal complication of LVAD therapy.

Mitesh V. Badiwala, M.D.
Heather J. Ross, M.D., M.H.Sc.
Vivek Rao, M.D., Ph.D.
Toronto General Hospital, Toronto, ON M5G 2C4, Canada
vivek.rao@uhn.on.ca

Citing Articles (3)

Citing Articles

1. 1

   Timothy N. Bachman, Jay K. Bhama, Josiah Verkaik, Stijn Vandenberghe, Robert L. Kormos, James F. Antaki. (2011) In Vitro Evaluation of Ventricular Cannulation for Rotodynamic Cardiac Assist Devices. Cardiovascular Engineering and Technology 2:3, 203-211
   CrossRef

2. 2

   Jay K. Bhama, Timothy N. Bachman, Robert L. Kormos, Harvey Borovetz, James F. Antaki. (2009) Development of an Ex Vivo Ovine Ventricular Assist Device Model for Intraventricular Visualization of the Inflow Cannula. The Journal of Heart and Lung Transplantation 28:8, 860-861
   CrossRef

3. 3

   Timothy J. Myers, Mathius Bolmers, Igor D. Gregoric, Biswajit Kar, O.H. Howard Frazier. (2009) Assessment of Arterial Blood Pressure During Support With an Axial Flow Left Ventricular Assist Device. The Journal of Heart and Lung Transplantation 28:5, 423-427
   CrossRef