The estimation of left ventricular function using prospective ECG-triggered coronary CT angiography

BACKGROUND

Coronary computed tomography angiography (CCTA) is vital for diagnosing coronary artery disease; however, prospective ECG-triggered acquisition, minimizing radiation exposure, limits left ventricular (LV) ejection fraction (EF) evaluation. We aimed to assess the feasibility and utility of LVEF100msec, a new index for estimating LV function using volumetric changes during 100 msec within systole.

METHODS

This retrospective study analyzed patients who underwent prospective ECG-triggered CCTA with systolic acquisition between January 2015 and June 2022. The LVEF100msec was calculated using the maximum and minimum LV volumes among the three phases (300, 350, and 400 msec post-QRS) and expressed as a percentage. Patients were classified into normal, mild-moderately reduced, or severely reduced LV function categories based on the reference test. The LVEF100msec was compared among groups, and the optimal cutoff value of LVEF100msec for predicting severe LV dysfunction was investigated.

RESULTS

The study included 271 patients (median age ​= ​58 years, 52% male). LVEF was normal in 188 (69.4%), mild-moderately reduced in 57 (21.0%), and severely reduced in 26 (9.6%) patients. Median LVEF100msec value was 9.0 (6.7-12.6) for normal LV function, 4.7 (3.1-8.8) for mild-moderately reduced, and 2.9 (1.5-3.8) for severely reduced LV function. LVEF100msec values significantly differed among categories (p ​< ​0.001). The optimal LVEF100msec cutoff for severe LV dysfunction was 4.3%, with an AUC of 0.924, sensitivity of 88%, and specificity of 89%.

CONCLUSION

The LVEF100msec may serve as a valuable indicator of severe LV dysfunction.

Subaortic Membrane With Mitral Chordae Rupture Mimicking Left Ventricular Outflow Tract Obstruction in Hypertrophic Cardiomyopathy

Hypertrophic cardiomyopathy (HCM) is an autosomal-dominant disorder that can lead to left ventricular outflow tract (LVOT) obstruction. Some patients present with syncope, dyspnea, chest pain, or sudden cardiac death. A subaortic membrane (SAM) is an unusual cause of ventricular outflow tract obstruction causing symptoms that can imitate HCM. It is essential to differentiate between these two entities, as it has important implications in guiding treatment and determining the type of intervention. Echocardiography is the gold standard modality for the diagnosis. In this report, we present a case of a 56-year-old man presenting with subaortic stenosis with ruptured mitral chordae misdiagnosed as HCM with SAM.

Role of Echocardiography in the Diagnosis of Light Chain Amyloidosis: A Case Report and Review of Literature

Amyloid light-chain (AL) amyloidosis is a rare disease with a broad clinical presentation that depends on the affected organ. Cardiac amyloidosis, a rare entity, can present as an isolated form of AL amyloidosis. This isolated form is considered a challenging diagnosis due to its broad nonspecific clinical presentation. In this article, we report a case of an adult male who presented with shortness of breath and was found to have many specific features of cardiac amyloidosis on echocardiography. In absence of other organ involvement, the results of the echocardiography directed us toward the diagnosis of AL cardiac amyloidosis. In addition, we highlight the role of echocardiography in the diagnosis of cardiac amyloidosis.