Altered myocardial glucose utilization and the reverse mismatch pattern on rubidium-82 perfusion/F-18-FDG PET during the sub-acute phase following reperfusion of acute anterior myocardial infarction.

BACKGROUND: Reperfused myocardium post-acute myocardial infarction (AMI) may have altered metabolism with implications for therapy response and function recovery. We explored glucose utilization and the "reverse mismatch" (RMM) pattern (decreased F-18-fluorodeoxyglucose (FDG) uptake relative to perfusion) in patients who underwent mechanical reperfusion with percutaneous coronary intervention (PCI) for AMI. METHODS AND RESULTS: Thirty-one patients with anterior wall AMI treated with acute reperfusion, with left ventricular ejection fraction ≤45%, underwent rest rubidium-82 (Rb-82) and FDG PET 2-10 days post-AMI. Resting echocardiograms were used to assess wall motion abnormalities. Significant RMM occurred in 15 (48%) patients and was associated with a shorter time to PCI of 2.9 hours (2.2, 13.3 hours) compared to patients without significant RMM: 11.4 hours (3.9, 22.4 hours) (P = .03). Within the peri-infarct regions, segments with significant RMM were more likely to have wall motion abnormalities (OR = 2.3 (1.1, 4.7), P = .02) compared to segments without significant RMM. CONCLUSIONS: RMM is a common pattern on perfusion/FDG PET during the sub-acute phase following reperfusion of AMI and is associated with shorter times to PCI. Within the peri-infarct region, RMM occurs frequently and is more often associated with wall motion abnormalities than segments without RMM. Whether this represents a myocardial metabolic shift during the sub-acute phase of recovery warrants further study.

Sleep apnea in chronic heart failure.

PURPOSE OF REVIEW: As heart failure continues to carry significant morbidity and mortality it is crucial to pursue new lines of therapy. Addressing sleep apnea, which is highly prevalent in these patients, offers just such an avenue. We discuss how sleep apnea may contribute to the propagation of heart failure, and how understanding its effects and reversing these effects might benefit heart failure patients. RECENT FINDINGS: Continuous positive airway pressure ventilation, atrial pacing, and chronic resynchronization therapy have all been studied in sleep apnea. Some of these therapies have shown benefits in heart failure. This offers hope for improved outcomes, particularly with respect to mortality. Delineating how these therapies affect the heart's energetics and metabolism may also provide further understanding of the relationship between sleep apnea and heart failure. SUMMARY: As both obstructive and central sleep apnea are highly prevalent in heart failure, treating these patients with continuous positive airway pressure, atrial pacing, or chronic resynchronization therapy may offer morbidity and mortality benefits. Much remains to be understood about the relationship between sleep apnea and heart failure, and understanding the interaction between the two at both the myocardial and clinical level is crucial.

New therapies in acute decompensated heart failure.

PURPOSE OF REVIEW: Hospitalization and mortality rates associated with heart failure are persistently high. This is due partly to aging of the population but mostly to delayed progress in the pharmacological treatment of decompensated heart failure. We will review the current recommendations and most recent advancement in the pharmacological treatment of acute decompensated heart failure while providing a systematic approach to the management of this prevalent condition. RECENT FINDINGS: Loop diuretics, nitrates and inotropes such as dobutamine and milrinone are the current mainstay of acute heart failure management although their associated morbidity and possible mortality have raised serious concerns. Recent vasoactive agents such as Nesiritide, Tolvaptan and more recently the inotropic agent Levosimedan could offer improved hemodynamics and congestive relief to patients in acute pulmonary edema. SUMMARY: Despite the promising results of these agents, further clinical trials are required prior to their international approval as first-line therapy. Although we can be optimistic that these vasoactive drugs might have favorable clinical outcomes and improve the intricate management of decompensated heart failure, their associated mortality benefit remains unclear and controversial.

Barriers to communication regarding end-of-life care: perspectives of care providers.

OBJECTIVE: Communication regarding end-of-life care is frequently perceived as suboptimal, despite the intent of both health care providers and patients. We interviewed health care providers to determine their perspective regarding these barriers to communication. MATERIALS AND METHODS: Eleven focus groups with a total of 10 attending physicians, 24 residents, and 33 nurses were convened to explore barriers to end-of-life discussions on the Internal Medicine service at a 600-bed tertiary care hospital in Toronto, Canada. An interview schedule was designed to elicit information regarding the process of end-of-life discussions, barriers to these discussions, and possible interventions for limiting such barriers. Transcripts were qualitatively analyzed by 6 raters who independently identified "themes." Themes were refined using the Delphi technique and classified under broader "categories." RESULTS: Four main categories of barriers emerged, relating to (1) patients, (2) the health care system, (3) health care providers, and (4) the nature of this dialogue. Attending physicians and residents most frequently identified patient-related factors as barriers to discussions, followed by system, dialogue, and provider barriers (43%, 39%, 10%, and 8%, respectively, for attending physicians; 40%, 34%, 13%, and 13%, respectively, for residents). Nurses similarly identified patient-related and system barriers most frequently, but provider barriers were discussed more often than dialogue barriers (46%, 28%, 22%, and 4%, respectively). CONCLUSIONS: Attending physicians, residents, and nurses perceive the recipients of their care, and the system within which they provide this care, to be the major source of barriers to communication regarding end-of-life care. This finding may impact on the effectiveness of quality-improvement initiatives in end-of-life care.