Amyloidosis is a clinical disorder caused by extracellular and or intracellular deposition of insoluble abnormal amyloid fibrils that alter the normal function of tissues. Amyloid A amyloidosis is the most common form of systemic amyloidosis worldwide The heart may be affected in systemic AL amyloidosis, but also more rarely in A amyloidosis.
In this report, we presented a patient with A-type amyloid heart disease who had dynamic left ventricular outflow tract obstruction mimicking hypertrophic obstructive cardiomyopathy. We also investigated left ventricular torsion, untwisting rate and left ventricular longitudinal global strain by two-dimensional speckle tracking echocardiography.
Amyloidosis is a clinical disorder caused by extracellular and/or intracellular deposition of insoluble abnormal amyloid fibrils that alter the normal function of tissues. Amyloid A (AA) amyloidosis is the most common form of systemic amyloidosis worldwide. In A amyloidosis, the kidneys, liver, and spleen are the major sites of involvement. The heart may be affected in systemic amyloid light chain amyloidosis, but also more rarely in AA amyloidosis.
In this report, we present the case of a patient with A-type amyloid heart disease who had dynamic left ventricular (LV) outflow tract (LVOT) obstruction mimicking hypertrophic obstructive cardiomyopathy (HOCM). We also investigated LV torsion, untwisting rate, and LV longitudinal global strain using two-dimensional speckle-tracking echocardiography.
A 33-year-old male patient with no known previous disorder was admitted to our hospital with the complaints of dyspnea, anorexia, nausea, and vomiting. On physical examination, his blood pressure was 110/70 mm Hg, and his pulse rate was rhythmic and 76 beats/min. He had a grade 1/6 systolic murmur along the left sternal border that increased with performance of the Valsalva maneuver and hepatosplenomegaly 2 cm. electrocardiography revealed normal sinus rhythm and T negativity in leads V 4 to V 6 derivations and down-sloping ST-segment depression. Hematologic results were normal. Biochemical investigation showed serum creatinine of 10.1 mg/dL, blood urea nitrogen of 70 mg/dL, sodium of 128 mEq/L, and potassium of 6.5 mEq/L, and blood gas analysis revealed metabolic acidosis. Urinalysis showed albuminuria (800 mg/L in 24 hours). To assess the clonality of immunoglobulins, serum protein electrophoresis and serum and urine immunoelectrophoresis were performed. We did not detect any amonoclonal antibodies. Renal ultrasonography showed bilaterally increased dimensions and echogenicity in the kidneys. On follow-up, the patient’s urine output decreased. He was scheduled for hemodialysis because of uremic symptoms, refractory acidosis, and hyperkalemia.
The patient improved after hemodialysis, and transthoracic echocardiography was performed. Echocardiography revealed that LV function was normal (ejection fraction, 60%), and there was minimal pericardial effusion and concentric LV hypertrophy (septal thickness, 2.6 cm; posterior wall thickness, 2.3 cm; LV mass index, 208 g/m 2 ); also, granular sparkling was widely observed, particularly on the interventricular septum ( Figure 1 , Video 1 ). Although there was no systolic anterior motion or premature closure of the aortic valve, we investigated the LVOT gradient because of the presence of septal thickness. There was a gradient across the LVOT of 20 mm Hg at rest and 75 mm Hg after performance of the Valsalva maneuver. Transmitral flow was found to be consistent with a restrictive pattern (ratio of transmitral early diastolic to late diastolic velocity, 2.7; deceleration time, 97 msec; E/E′ ratio, 21; flow propagation velocity, 23 cm/sec; Figure 2 ). In addition, LV torsion was 8°, peak basal rotation was −2.4°, peak untwisting velocity was 25°/sec, and LV longitudinal global strain was −7 on speckle-tracking echocardiography ( Figures 3 A and 3 B and Videos 2 and 3 ). To evaluate right ventricular systolic function globally, tricuspid annular motion was assessed and found to be 2.3 cm ( Figure 4 ).