The normal aging process is often accompanied by arterial wall stiffening and by a decrease in myocardial compliance. These processes contribute to isolated systolic hypertension and diastolic heart failure, which lead to substantial morbidity and mortality among older individuals. Patients with diabetes manifest arterial stiffening and diastolic dysfunction at a younger age. This leads to the concept that the mechanism that underlies changes in vascular mechanical properties during aging is accelerated in diabetes. The Maillard reaction or advanced glycation of proteins occurs slowly in vivo with normal aging and at an accelerated rate in diabetes. Advanced glycation end-products (AGEs) that form during the Maillard reaction are implicated in the complications of aging and diabetes. The formation of AGEs on vascular wall and myocardial collagen causes cross-linking of collagen molecules to each other. This leads to the loss of collagen elasticity, and subsequently a reduction in arterial and myocardial compliance. Aminoguanidine, an inhibitor of AGE formation, is effective in slowing or preventing arterial stiffening and myocardial diastolic dysfunction in aging and diabetic animals. In aged and diabetic animals, agents that can chemically break pre-existing cross-linking of collagen molecules are capable of reverting indices of vascular and myocardial compliance to levels seen in younger or non-diabetic animals. These studies suggest that collagen cross-linking is a major mechanism that governs aging and diabetes-associated loss of vascular and cardiac compliance. The development of AGEs cross-link breakers may have important role for future therapy of isolated systolic hypertension and diastolic heart failure in these conditions.

Patients with diabetes mellitus (DM) are prone to a diffuse and rapidly progressive form of atherosclerosis, which increases their likelihood of requiring revascularization. However, the unique pathophysiology of atherosclerosis in patients with DM modifies the response to arterial injury, with profound clinical consequences for patients undergoing percutaneous coronary intervention (PCI). Multiple studies have shown that DM is a strong risk factor for restenosis following successful balloon angioplasty or coronary stenting, with greater need for repeat revascularization and inferior clinical outcomes. Early data suggest that drug eluting stents reduce restenosis rates and the need for repeat revascularization irrespective of the diabetic state and with no significant reduction in hard clinical endpoints such as myocardial infarction and mortality. For many patients with 1- or 2-vessel coronary artery disease, there is little prognostic benefit from any intervention over optimal medical therapy. PCI with drug-eluting or bare metal stents is appropriate for patients who remain symptomatic with medical therapy. However, selection of the optimal myocardial revascularization strategy for patients with DM and multivessel coronary artery disease is crucial. Randomized trials comparing multivessel PCI with balloon angioplasty or bare metal stents to coronary artery bypass grafting (CABG) consistently demonstrated the superiority of CABG in patients with treated DM. In the setting of diabetes CABG had greater survival, fewer recurrent infarctions or need for re-intervention. Limited data suggests that CABG is superior to multivessel PCI even when drug-eluting stents are used. Several ongoing randomized trials are evaluating the long-term comparative efficacy of PCI with drug-eluting stents and CABG in patients with DM. Only further study will continue to unravel the mechanisms at play and optimal therapy in the face of the profoundly virulent atherosclerotic potential that accompanies diabetes mellitus.

Significant tricuspid regurgitation (TR) is common in heart failure (HF) and portends poor prognosis. We sought to determine whether the poor outcome results from the TR itself, or whether the TR is a surrogate marker of advanced left-sided myocardial or valvular heart disease. We studied 639 patients admitted for acute HF. The relationship between TR severity and the endpoint of readmission for HF or mortality was assessed after adjustment for multiple clinical and echocardiographic parameters. Higher TR grade was associated with higher congestion score and with other cardiac abnormalities including reduced left ventricular systolic function, moderate or severe mitral regurgitation, pulmonary hypertension (PH, defined as pulmonary artery systolic pressure ≥ 50 mmHg), and right ventricular dysfunction (all P < 0.001). Only 7% of patients with moderate or severe TR were free of other cardiac lesions. In adjusted models, moderate or severe TR was not associated with readmission for HF or mortality [hazard ratio (HR) 1.24, 95% confidence interval (95% CI) 0.97–1.57]. Patients with moderate/severe TR had similar risk for HF readmission or death compared with patients with trivial/mild TR when PH was not present (HR 1.17; 95% CI 0.78–1.75, P = 0.40) whereas the risk was higher in moderate/severe TR and PH (HR 1.78; 95% CI 1.34–2.36, P < 0.0001). Patients presenting with symptomatic HF and significant TR have multiple coexisting cardiac abnormalities. TR provides no additive risk in the presence of normal or mildly elevated pulmonary pressures. However, it is associated with excess rehospitalizations and mortality in patients with PH.