Prevalence of amyloid deposition in patients undergoing surgical myectomy for presumed hypertrophic cardiomyopathy.

BACKGROUND

Cardiac amyloidosis (CA) and hypertrophic cardiomyopathy (HCM) share the phenotypic characteristic of increased left ventricular wall thickness and, while more common with HCM, both conditions can result in dynamic left ventricular outflow (LVOT) obstruction. We sought to examine the incidence of amyloid deposition in myectomy specimens at a high-volume center for surgical myectomy and describe the pathologic characteristics and patient population.

METHODS AND

RESULTS

We reviewed the surgical myectomy database at our institution and found a total of 27 of 3,292 (0.8 %) with cardiac amyloidosis on pathologic examination of myectomy specimens. Many of these had preoperative imaging features consistent with hypertrophic cardiomyopathy with asymmetric hypertrophy and LVOT obstructive physiology.

CONCLUSION

Nearly 1 % of patients referred for surgical myectomy were found to have unexpected amyloid deposits on pathologic examination. Recognition of this finding, although very infrequent, is important for long-term management of these patients.