Magnetic resonance imaging of dilated cardiomyopathy: prognostic benefit of identifying late gadolinium enhancement in Asian patients

INTRODUCTION@#Risk stratification in dilated cardiomyopathy (DCM) is imprecise, relying largely on echocardiographic left ventricular ejection fraction (LVEF) and severity of heart failure symptoms. Adverse cardiovascular events are increased by the presence of myocardial scarring. Late gadolinium enhancement (LGE) on cardiovascular magnetic resonance (CMR) imaging is the gold standard for identifying myocardial scars. We examined the association between LGE on CMR imaging and adverse clinical outcomes during long-term follow-up of Asian patients with DCM.@*METHODS@#Consecutive patients with DCM undergoing CMR imaging at a single Asian academic medical centre between 2005 and 2015 were recruited. Clinical outcomes were tracked using comprehensive electronic medical records and mortality was determined by cross-linkages with national registries. Presence and distribution of LGE on CMR imaging were determined by investigators blinded to patient outcomes. Primary endpoint was a composite of heart failure hospitalisations, appropriate implantable cardioverter-defibrillator shocks and cardiovascular mortality.@*RESULTS@#Of 86 patients, 64.0% had LGE (80.2% male; mean LVEF 30.1% ± 12.7%). Mid-wall fibrosis (71.7%) was the most common pattern of LGE distribution. Over a mean follow-up period of 4.9 ± 3.2 years, 19 (34.5%) patients with LGE reached the composite endpoint compared to 4 (12.9%) patients without LGE (p = 0.01). Presence of LGE, but not echocardiographic LVEF, independently predicted the primary endpoint (hazard ratio 4.15 [95% confidence interval 1.28-13.50]; p = 0.02).@*CONCLUSION@#LGE presence independently predicted adverse clinical events in Asian patients with DCM. Routine use of CMR imaging to characterise the myocardial substrate is recommended for enhanced risk stratification and should strongly influence clinical management.

A practical and adaptive approach to lung cancer screening: a review of international evidence and position on CT lung cancer screening in the Singaporean population by the College of Radiologists Singapore

Lung cancer is the leading cause of cancer-related death around the world, being the top cause of cancer-related deaths among men and the second most common cause of cancer-related deaths among women in Singapore. Currently, no screening programme for lung cancer exists in Singapore. Since there is mounting evidence indicating a different epidemiology of lung cancer in Asian countries, including Singapore, compared to the rest of the world, a unique and adaptive approach must be taken for a screening programme to be successful at reducing mortality while maintaining cost-effectiveness and a favourable risk-benefit ratio. This review article promotes the use of low-dose computed tomography of the chest and explores the radiological challenges and future directions.

Clinics in diagnostic imaging (186). Atrial septal defect with pulmonary arterial hypertension

We report a case of a 61-year-old woman with a large atrial septal defect (ASD) that was detected incidentally on chest radiography and computed tomography when she presented with sepsis. Echocardiography confirmed a large secundum ASD with left-to-right shunt flow, right heart dilatation and severe pulmonary hypertension. The patient had a poor clinical outcome despite intensive care and eventually passed away. Haemodynamically significant ASDs have a known association with increased morbidity and mortality, and their early detection and closure cannot be understated. This article aimed to highlight the imaging features of ASD, with special emphasis on the routine chest radiograph. The pathophysiology and clinical manifestations of ASD are also briefly discussed.

Clinics in diagnostic imaging (155). Incidental PDA with secondary pulmonary arterial hypertension

We report the case of a 70-year-old man with an asymptomatic large patent ductus arteriosus (PDA) incidentally detected on triple-rule-out computed tomography (CT). CT clearly demonstrated a vascular structure connecting the descending thoracic aorta to the roof of the proximal left pulmonary artery, consistent with a PDA. Secondary pulmonary arterial hypertension was also evident on CT. The patient was eventually diagnosed with acute coronary syndrome and was successfully treated with coronary artery bypass graft surgery and concomitant patch closure of the PDA. This article aims to outline the imaging features of PDA and highlight the information provided by CT, which is crucial to treatment planning. The pathophysiology, clinical manifestations and closure options of PDA are also briefly discussed.