Hyperoxic vasoconstriction of human pulmonary arteries: a novel insight into acute ventricular septal defects.

Objectives. Acute rises in pulmonary artery pressures following postinfarction ventricular septal defects present a challenge. We hypothesised that the abnormally high oxygen content exposure to the pulmonary arteries may be a factor.

Research report: the effects of hyperbaric oxygen preconditioning on myocardial biomarkers of cardioprotection in patients having coronary artery bypass graft surgery.

We have previously conducted and reported on the primary endpoint of a clinical study which demonstrated that hyperbaric oxygen (HBO2) preconditioning consisting of two 30-minute intervals of 100% oxygen at 2.4 atmospheres absolute (ATA) prior to coronary artery bypass graft (CABG) surgery leads to an improvement in left ventricular stroke work (LVSW) 24 hours following CABG. In that study, 81 patients were randomized to treatment with HBO2 (HBO2; n = 41) or routine treatment (Control Group; n = 40) prior to surgery.

Hyperbaric oxygen preconditioning improves myocardial function, reduces length of intensive care stay, and limits complications post coronary artery bypass graft surgery.

Objective: The objective of this study was to determine whether preconditioning coronary artery disease (CAD) patients with HBO(2) prior to first-time elective on-pump cardiopulmonary bypass (CPB) coronary artery bypass graft surgery (CABG) leads to improved myocardial left ventricular stroke work (LVSW) post CABG. The primary end point of this study was to demonstrate that preconditioning CAD patients with HBO(2) prior to on-pump CPB CABG leads to a statistically significant (P<.05) improvement in myocardial LVSW 24 h post CABG.

Aprotinin in primary cardiac surgery: operative outcome of propensity score-matched study.

Background: Some recent multicenter series have questioned the safety of aprotinin in primary cardiac operations. We report a large, single-center experience with aprotinin therapy in primary cardiac operations and discuss the limitations and potential confounders of current treatment strategies.

Methods: We compared myocardial infarction, neurologic events, renal insufficiency, and operative death after first-time coronary or valve procedures, or both, in 3334 patients treated with full-dose aprotinin with 3417 patients not treated with aprotinin who underwent operation between March 1998 and January 2007.

Are initial valve operations in octogenarians still high-risk in the current era?

Background And Aim Of The Study: The average age of cardiac patients continues to increase. As more octogenarians undergo surgery during the current era, the outcome of valve surgery was investigated to determine the operative risk in these patients.

Methods: Among 350 patients aged > or = 80 years who had initial surgery between 1998 and 2006, a total of 188 (105 females, 83 males) underwent valve surgery.

Early and late survival after surgical revascularization for ischemic ventricular fibrillation/tachycardia.

Background: Ischemic ventricular fibrillation/tachycardia (VF/VT) treated by myocardial revascularization, often with an implanted cardioverter defibrillator, prevents sudden cardiac death. Early series have suggested that recurrent VF/VT threatens survival even after treatment. As late outcome is unknown, we sought to determine if the early survival benefit is sustained.

Is post-sternotomy percutaneous dilatational tracheostomy a predictor for sternal wound infections?

Objective: Early post-sternotomy tracheostomy is not infrequently considered in this era of percutaneous tracheostomy. There is, however, some controversy about its association with sternal wound infections.

Methods: Consecutive patients who had percutaneous tracheostomy following median sternotomy for cardiac operation at our institution from March 1998 through January 2007 were studied, and compared to contemporaneous patients.

Early neurological complications after coronary artery bypass grafting and valve surgery in octogenarians.

Objective: To determine the incidence and risk factors for neurological events complicating cardiac surgery, and the implications for operative outcome in octogenarians.

Methods: Of 6791 who underwent primary on-pump CABG and/or valve surgery from 1998 through 2006, 383 were aged > or =80 years. Neurological complications, classified as reversible or permanent, were investigated by head CT scan in patients who did not recover soon after an event.

The impact of symptom severity on cardiac reoperative risk: early referral and reoperation is warranted.

Background: Operative mortality is comparatively higher for coronary artery bypass grafting (CABG) or valve reoperations. Studies of reoperative risk have focussed on surgical techniques. We sought to determine the risk and predictors of poor outcome in current practice, and the influence of preoperative symptoms.

Can hyperbaric oxygen be used as adjunctive heart failure therapy through the induction of endogenous heat shock proteins?

Heart failure (HF) is a chronic condition that is expected to increase in incidence along with increased life expectancy and an aging population. As the incidence of HF increases, the cost to national healthcare budgets is expected to run into the billions. The costs of lost productivity and increased social reliance on state support must also be considered.

Hyperbaric oxygen: a novel technology for modulating myocardial schemia-reperfusion via a single drug.

Over the years, the anecdotal medical use of oxygen has demonstrated, in a non-evidence-based manner, that it may have wide-ranging clinical consequences. Although oxygen is a critical substrate in the alleviation of hypoxia, anoxia, and ischemia, paradoxically, it also functions as a deleterious metabolite during the reperfusion of previously ischemic tissues. In adding to this controversy, a spate of new pioneering work has identified hyperoxygenation (hyperoxia) and its metabolites as solely and purposefully demonstrating cellular and clinical benefit,particularly in the field of ischemic reperfusion injury (IRI).

Hyperbaric oxygen: a new drug in myocardial revascularization and protection?

Ischemia-reperfusion injury (IRI) occurs following coronary artery revascularization. Reactive oxygen species (ROS) were initially thought to play a role in the pathogenesis of this injury. However, the evidence for this is inconclusive.

Randomized comparison of stentless versus stented valves for aortic stenosis: effects on left ventricular mass.

Background: Aortic valve replacement (AVR) is the established treatment for severe aortic stenosis. In response to the long-term results of aortic homografts, stentless porcine valves were introduced as an alternative low-resistance valve. We conducted a randomized trial comparing a stentless with a stented porcine valve in adults with severe aortic stenosis.