Prospective peer review of regional percutaneous interventional procedures: a tool for quality control and revalidation.

AIMS: Current quality measures of percutaneous coronary intervention (PCI) procedures are based on the incidence of major adverse cardiac events (MACE). This crude marker ignores the many clinical nuances that make for sound decision making in PCI. We have established a prospective peer review audit tool to determine the quality of PCI within our cardiac network, which consists of five PCI hospitals serving a population of 1.4 million people in Sussex, UK. METHODS AND RESULTS: Analysis of 10% of all PCI cases selected at random each month by a non-clinical audit manager is made by a rotating panel of two PCI operators and one cardiac surgeon. Each PCI case is assessed for anatomical suitability, lesion severity, strategic appropriateness and final outcome. Panel findings were reported back to the operator and the audit manager. A total of 326 cases were assessed by the review committee. Results were disseminated to individual operators. Coronary anatomy and lesion severity were considered appropriate for PCI in 94.2% and 96.0% of cases, respectively. Appropriateness of strategy was confirmed in 86.2% and the outcome considered satisfactory in 90.8%. A total of 242 subsequent cases were analysed to assess practice trends. This analysis demonstrated a statistically significant improvement in clinical decision making with respect to appropriateness of strategy (from 86.2% to 92.6%; p=0.004). CONCLUSIONS: Prospective peer review of percutaneous coronary intervention cases by a rotating regional committee is valuable in ensuring procedural quality.

Rescue angioplasty for failed fibrinolysis--long-term follow-up of a large cohort.

BACKGROUND: Fibrinolysis remains an important treatment for ST-elevation myocardial infarction, but fails to achieve adequate reperfusion in a significant proportion of cases. "Rescue" angioplasty is seen as the preferred treatment strategy in most contemporary centers although the literature provides conflicting evidence. METHODS: We retrospectively reviewed all cases of rescue angioplasty performed at our cardiothoracic center from July 1999 to June 2008. The diagnosis of failed lysis was made on the basis of an ECG demonstrating failure of ST segment resolution >50% at 90 min. Periprocedural data was taken from a dedicated procedural database and mortality data obtained from the UK Office of National Statistics. RESULTS: A total of 316 cases were performed. Patients were aged 61 ± 11 years. Thirty-day mortality was 8.9%. Thirty-day mortality in those presenting with cardiogenic shock was 50%, and in those requiring blood transfusion was also 50%. Thirty day mortality in those with TIMI III flow at the end of the procedure was significantly less than in those in whom this was not the case (6.6% vs. 23.3%; P < 0.001). One year mortality for the entire cohort was 10.1%. Longer-term follow-up revealed after 5.2 ± 2.3 years, survival in this cohort was 83%. Significant bleeding requiring blood transfusion occurred in 2.5% of cases. CONCLUSIONS: We have shown that rescue angioplasty can be performed with good procedural success rates and excellent long-term results. Limiting bleeding complications and achieving TIMI III flow appear to be major determinants of achieving good long term results.

Chronic oral ascorbic acid therapy worsens skeletal muscle metabolism in patients with chronic heart failure.

BACKGROUND: Chronic heart failure (CHF) is associated with abnormalities of skeletal muscle metabolism. This may be due to impaired oxygen delivery as a result of endothelial dysfunction. AIMS: We postulated that ascorbic acid would improve oxygen delivery to exercising muscle and improve skeletal muscle metabolism. METHODS: We studied skeletal muscle metabolism using (31)P magnetic resonance spectroscopy in 39 CHF patients. Endothelial function was assessed by changes in pulse wave velocity. Subjects were randomised to receive 4 g ascorbic acid daily for 4 weeks in a placebo-controlled double-blind study. RESULTS: Ascorbic acid significantly increased phosphocreatine utilization during exercise. In addition, glycolytic ATP synthesis increased in the ascorbic acid group (change in rate of ATP synthesis at 1 min -0.21+/-0.76 with placebo, 2.06+/-0.60 following ascorbic acid; p<0.05). Phosphocreatine and ADP recovery after exercise were not changed. The fall in pulse wave velocity during reactive hyperaemia was increased by ascorbic acid from -6.3+/-2.6% to -12.1+/-2.0% (p<0.05). CONCLUSIONS: These findings suggest that ascorbic acid increased both phosphocreatine utilization and glycolytic ATP synthesis during exercise in patients with CHF implying worsened skeletal muscle metabolism despite improvements in endothelial function.

Role of nitric oxide and oxidative stress in baroreceptor dysfunction in patients with chronic heart failure.

Abnormalities of autonomic control of the cardiovascular system are seen in chronic heart failure (CHF) and confer a poor prognosis. Nitric oxide appears to be important in the regulation of baroreflex control in health and in disease states. The antioxidant vitamin C increases nitric oxide bioavailability in CHF. We evaluated the effects of vitamin C on baroreceptor sensitivity (BRS) by sequence analysis in 100 CHF patients and 44 control subjects. Groups of 55 CHF patients and 22 controls were randomly allocated to receive a single intravenous injection of vitamin C (2 g) or placebo. In addition, 45 CHF patients were randomly allocated to receive a 4-week course of oral vitamin C (4 g/day) or placebo. An age-related reference range for BRS was developed in 22 healthy controls matched for age and gender to the CHF group. BRS was significantly impaired in the CHF group compared with age-matched older controls and young controls (6.9 +/- 3.1, 12.5 +/- 4.9 and 21.7 +/- 9.1 mmHg/ms respectively; P < 0.001 between groups). Intravenous vitamin C acutely improved BRS in CHF patients by 24% (by 1.8 +/- 4.1 mmHg/ms; P < 0.05), but not in controls. There was no improvement in BRS in CHF patients given chronic oral vitamin C. Thus acute intravenous, but not chronic oral, vitamin C improved BRS in CHF patients. There was no effect of intravenous vitamin C in healthy subjects, suggesting that the mechanism was either by free radical scavenging or due to central effects.

UK Food Standards Agency alpha-linolenic acid workshop report.

The UK Food Standards Agency convened a group of expert scientists to review current research investigating whether n-3 polyunsaturated fatty acids (PUFA) from plant oils (alpha-linolenic acid; ALA) were as beneficial to cardiovascular health as the n-3 PUFA from the marine oils, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). The workshop also aimed to establish priorities for future research. Dietary intake of ALA has been associated with a beneficial effect on CHD; however, the results from studies investigating the effects of ALA supplementation on CHD risk factors have proved equivocal. The studies presented as part of the present workshop suggested little, if any, benefit of ALA, relative to linoleic acid, on risk factors for cardiovascular disease; the effects observed with fish-oil supplementation were not replicated by ALA supplementation. There is a need, therefore, to first prove the efficacy of ALA supplementation on cardiovascular disease, before further investigating effects on cardiovascular risk factors. The workshop considered that a beneficial effect of ALA on the secondary prevention of CHD still needed to be established, and there was no reason to look further at existing CHD risk factors in relation to ALA supplementation. The workshop also highlighted the possibility of feeding livestock ALA-rich oils to provide a means of increasing the dietary intake in human consumers of EPA and DHA.