A case of systemic sclerosis with worsened subclinical left ventricular systolic dysfunction after pacemaker implantation

Abstract

A 58-year-old man suffering from systemic sclerosis was admitted to our hospital because of heart failure. He developed atrioventricular block 4 months previously and had a pacemaker implanted, after which left ventricular wall motion markedly worsened. The global longitudinal strain was already decreased before the onset of atrioventricular block, although the left ventricular ejection fraction was normal. Right ventricular pacing was suspected to have caused overt left ventricular systolic dysfunction. Therefore, right ventricular pacing was upgraded to cardiac resynchronization therapy. After this change, the left ventricular ejection fraction improved to almost normal, but global longitudinal strain remained decreased. The findings in our case suggest that some patients with systemic sclerosis already have subclinical left ventricular systolic dysfunction before the onset of atrioventricular block. Additionally, right ventricular pacing may cause further deterioration of left ventricular systolic function and heart failure.

Learning objective: The possibility of subclinical left ventricular systolic dysfunction associated with systemic sclerosis should be considered when implanting a pacemaker. Speckle-tracking echocardiography may also be useful in the management of patients with systemic sclerosis.

Keywords: Atrioventricular block; Cardiac resynchronization therapy; Heart failure; Left ventricular systolic dysfunction; Speckle-tracking echocardiography; Systemic sclerosis.

Fig. 1

(A) Electrocardiogram 4 months before admission showing advanced atrioventricular block with escape beats. (B) Electrocardiogram after pacemaker implantation. (C) Electrocardiogram after upgrading to cardiac resynchronization therapy.

Fig. 2

Left ventricular longitudinal strain and Bull's eye mapping by two-dimensional speckle-tracking echocardiography at 16 months before admission, 10 months before admission, and on admission. The white dotted line shows GLS in each view. AP4CH, apical four-chamber view; APLAX, apical long-axis view; AP2CH, apical two-chamber view; GLS, global longitudinal strain.

Fig. 3

Clinical course of the patient. The solid and dotted lines show the trends in the LVEF and GLS, respectively. GLS declined before the decline in the LVEF 10 months before admission. In addition, the trend of each left ventricular diastolic function index is shown below the graph. Four months before admission, we could not measure them due to AVB. A, late transmitral flow velocity; AVB, atrioventricular block; Ave, averaged; CAG, coronary angiography; CRT, cardiac resynchronization therapy; E, early transmitral flow velocity; e′, early diastolic mitral annular velocity; GLS, global longitudinal strain; LVEF, left ventricular ejection fraction; NA, not available; TRV, tricuspid regurgitant velocity.