Diabetes Mellitus Associates with Increased Right Ventricular Afterload and Remodeling in Pulmonary Arterial Hypertension.

BACKGROUND: Diabetes mellitus is associated with left ventricular hypertrophy and dysfunction. Parallel studies have also reported associations between diabetes mellitus and right ventricular dysfunction and reduced survival in patients with pulmonary arterial hypertension. However, the impact of diabetes mellitus on the pulmonary vasculature has not been well characterized. We hypothesized that diabetes mellitus and hyperglycemia could specifically influence right ventricular afterload and remodeling in patients with Group I pulmonary arterial hypertension, providing a link to their known susceptibility to right ventricular dysfunction. METHODS: Using an adjusted model for age, sex, pulmonary vascular resistance, and medication use, associations of fasting blood glucose, glycated hemoglobin, and the presence of diabetes mellitus were evaluated with markers of disease severity in 162 patients with pulmonary arterial hypertension. RESULTS: A surrogate measure of increased pulmonary artery stiffness, elevated pulmonary arterial elastance (P = .012), along with reduced log(pulmonary artery capacitance) (P = .006) were significantly associated with the presence of diabetes mellitus in patients with pulmonary arterial hypertension in a fully adjusted model. Similar associations between pulmonary arterial elastance and capacitance were noted with both fasting blood glucose and glycated hemoglobin. Furthermore, right ventricular wall thickness on echocardiography was greater in pulmonary arterial hypertension patients with diabetes, supporting the link between right ventricular remodeling and diabetes. CONCLUSION: Cumulatively, these data demonstrate that an increase in right ventricular afterload, beyond pulmonary vascular resistance alone, may influence right ventricular remodeling and provide a mechanistic link between the susceptibility to right ventricular dysfunction in patients with both diabetes mellitus and pulmonary arterial hypertension.

From bone to heart: a case of MRSA osteomyelitis with haematogenous spread to the pericardium.

We report a case of a 55-year-old woman with a history of type 2 diabetes mellitus, Charcot arthropathy and end-stage renal disease, who presented with a syncopal episode after undergoing haemodialysis. She had a history of methicillin-resistant Staphylococcus aureus (MRSA) bacteraemia from an unknown source 3 months earlier, which was treated with an 8-week course of intravenous antibiotics. At the time of presentation to the emergency room, she was found to be in refractory shock. Bedside echocardiogram was performed, which showed moderate pericardial effusion. The effusion was later found to be due to MRSA, which was identified in blood and in pericardial fluid cultures. The patient was successfully treated with intravenous daptomycin for 6 weeks. Acute osteomyelitis of her right foot was the source of the MRSA, for which a right below-knee amputation was ultimately performed.

Dissecting the unspeakable: a fatal case of aortic dissection.

A 47-year-old man with diabetes and hypertension presented with sudden onset of chest pain and subsequently developed expressive aphasia. Brain imaging revealed multiple areas of ischaemic infarcts. Transoesophageal echocardiogram revealed aortic dissection with a free-floating thrombus on the dissection flap, which was the source of emboli. Given the poor prognosis, surgical intervention was not pursued and artificial support was withdrawn. Aortic dissection is a highly fatal condition with varied presentation including heart failure, myocardial infarction, neurological deficits, abdominal pain or acute renal failure. Aortic dissection is a relatively uncommon but catastrophic condition. A high degree of clinical suspicion is required for early and accurate diagnosis since mortality is high and increases by the hour. The mechanism for stroke in our case was due to an artery-to-artery embolism from a thrombus, which developed on the intimal surface of the dissected artery. This is an infrequent complication with a very unique mechanism.