Premature Ventricular Contractions Producing Brockenbrough-Braunwald Sign in Obstructive Cardiomyopathy

J INVASIVE CARDIOL 2017;29(7):E83.

Key words: hypertrophic obstructive cardiomyopathy, Brockenbrough-Braunwald sign, aortic stenosis, pressure tracings

We present the case of a 76-year-old woman with history of aortic stenosis. Her only symptom was shortness of breath. She underwent an elective left and right heart catheterization with left ventricular and coronary angiogram. The results of the angiogram showed that she had normal coronary arteries and hypertrophic obstructive cardiomyopathy (HOCM), as the intracardiac hemodynamics were consistent with dynamic left ventricle outflow tract gradient of 42 mm Hg. She was started on aggressive medical therapy with beta-blocker; if her symptoms were refractory to medical therapy, she would be considered for ethanol septal ablation therapy. 

Hypertrophic cardiomyopathy is the most common hereditary disease of the heart. It has two sub-types, ie, non-obstructive and obstructive, with the latter being the more common type.¹ HOCM is classically associated with systolic anterior motion of the mitral valve leaflet and dynamic left ventricular outflow tract obstruction, which occurs when blood flows with higher velocities through a narrowed left ventricular outflow tract during the beginning of systole.² Increased dynamic flow in HOCM depicts a classic sign on invasive pressure tracings of the aorta and left ventricle, simultaneously known as Brockenbrough-Braunwald sign. The classical pattern is a decrease in pulse pressure and an increase in the peak-systolic gradient after a premature ventricular contraction (PVC). This pattern on pressure tracing directly correlates with the physical exam finding as a decrease in the pulse-pressure post-PVC beat in HOCM patients. This is secondary to the decreased stroke volume caused by the increased outflow tract obstruction.³ This is typically evident on the first sinus beat after a PVC (Figure 1).

References

1.    Prinz C, et al. The Diagnosis and Treatment of Hypertrophic Cardiomyopathy. Deutsches Ärzteblatt International 108.13. 2011:209-215. PMC. Accessed Mar 22, 2017.

2.    Braunwald E, Wigle ED. Idiopathic hypertrophic subaortic stenosis. Chest. 1973;64:222-224.

3.    Pollock SG. Pressure tracings in obstructive cardiomyopathy. N Engl J Med. 1994;331:238.

From the Department of Cardiovascular Medicine, Mercy Hospital & Medical Center, Chicago, Illinois.

Disclosure: The authors have completed and returned the ICMJE Form for Disclosure of Potential Conflicts of Interest. The authors report no conflicts of interest regarding the content herein.

Manuscript accepted March 29, 2017.

Address for correspondence: Gaurav K. Sharma, MD, Department of Medicine, 2525 South Michigan Ave, Chicago, IL 60616. Email: gauravsk6@yahoo.com