Inter-Ethnic Differences in Quantified Coronary Artery Disease Severity and All-Cause Mortality among Dutch and Singaporean Percutaneous Coronary Intervention Patients.

BACKGROUND: Coronary artery disease (CAD) is a global problem with increasing incidence in Asia. Prior studies reported inter-ethnic differences in the prevalence of CAD rather than the severity of CAD. The angiographic "synergy between percutaneous coronary intervention (PCI) with taxus and cardiac surgery" (SYNTAX) score quantifies CAD severity and predicts outcomes. We studied CAD severity and all-cause mortality in four globally populous ethnic groups: Caucasians, Chinese, Indians and Malays. METHODS: We quantified SYNTAX scores of 1,000 multi-ethnic patients undergoing PCI in two tertiary hospitals in the Netherlands (Caucasians) and Singapore (Chinese, Indians and Malays). Within each ethnicity we studied 150 patients with stable CAD and 100 with ST-elevated myocardial infarction (STEMI). We made inter-ethnic comparisons of SYNTAX scores and all-cause mortality. RESULTS: Despite having a younger age (mean age Indians: 56.8 and Malays: 57.7 vs. Caucasians: 63.7 years), multivariable adjusted SYNTAX scores were significantly higher in Indians and Malays than Caucasians with stable CAD: 13.4 [11.9-14.9] and 13.4 [12.0-14.8] vs. 9.4 [8.1-10.8], p<0.001. Among STEMI patients, SYNTAX scores were highest in Chinese and Malays: 17.7 [15.9-19.5] and 18.8 [17.1-20.6] vs. 15.5 [13.5-17.4] and 12.7 [10.9-14.6] in Indians and Caucasians, p<0.001. Over a median follow-up of 709 days, 67 deaths (stable CAD: 37, STEMI: 30) occurred. Among STEMI patients, the SYNTAX score independently predicted all-cause mortality: HR 2.5 [1.7-3.8], p<0.001 for every 10-point increase. All-cause mortality was higher in Indian and Malay STEMI patients than Caucasians, independent of SYNTAX score (adjusted HR 7.2 [1.5-34.7], p=0.01 and 5.8 [1.2-27.2], p=0.02). CONCLUSION: Among stable CAD and STEMI patients requiring PCI, CAD is more severe in Indians and Malays than in Caucasians, despite having a younger age. Moreover, Indian and Malay STEMI patients had a greater adjusted risk of all-cause mortality than Caucasians, independent of SYNTAX score.

Renal function and anaemia in acute myocardial infarction.

BACKGROUND: Impaired renal function and anaemia are common among patients with acute myocardial infarction (AMI). While both conditions are known independent risk factors for increased mortality, their interaction as risk factors for increased mortality in AMI is unclear. METHODS: We studied 5395 subjects hospitalized for AMI between January 2000 and December 2005. An estimated glomerular filtration rate (GFR) <60 mL/min/1.73 m(2) was defined as impaired GFR and GFR ≥ 60 mL/min/1.73 m(2) was defined as preserved GFR. Anaemia was defined as <13 g/dL (males) and <12 g/dL (females). The odds ratio (OR) for one-year mortality and its 95% confidence interval (CI) were calculated by logistic regression. RESULTS: We identified 758 (14%) patients with impaired GFR and anaemia, 1105 (20.5%) patients with impaired GFR without anaemia, 465 (8.6%) patients with preserved GFR and anaemia, and 3012 (55.8%) patients with preserved GFR without anaemia; one-year mortality rates were 56.5%, 41.8%, 31.8% and 10.3% respectively in these 4 groups. Among patients with impaired GFR, anaemia was associated with an adjusted OR of 1.47 (95% CI=1.17-1.85) for one-year mortality, while among patients with preserved GFR, anaemia was associated with a higher adjusted OR of 2.07 (95% CI=1.54-2.76) for one-year mortality, interaction P<0.001. CONCLUSION: The combination of impaired GFR and anaemia confers greater than five-fold increased risk of mortality after AMI. The differential effect of anaemia among patients with impaired and preserved GFR on mortality suggests that in patients with preserved GFR anaemia confers a greater relative hazard than in patients with impaired renal function.

Hydrodynamics- and ultrasound-based transfection of heart with naked plasmid DNA.

A novel, efficient transfection method, based on ultrasound and hydrodynamics, has been developed to transfect heart tissue with plasmid DNA. An ultrasound probe was aimed at the heart of anesthetized rats for 30 sec, at an intensity of 1 MHz and 2 W/cm2. The aorta was clamped and a phosphate-buffered saline (PBS) solution containing pSV-LacZ was quickly injected into the left ventricle. Each animal was maintained in this condition for 20 sec, and then the clamp was opened and the needle was removed. Electrocardiography, performed after 4 weeks, showed mild or no sign of ischemia in all groups. Visual evaluation of heart tissue samples from rats that received 100 microg of pSV-LacZ in 100 microl had only a few blue cells, indicating transfection, and those that received only PBS had no blue cells. However, all heart tissue samples from rats transfected with 100 to 500 microg of pSV-LacZ in 200 microl, or with 200 to 500 microg of pSV-LacZ in 100 micro had many blue cells. The base and epicardium of the heart tissue samples had many more blue cells than did the rest of the samples. Histological results, based on staining with hematoxylin and eosin, showed similar results between control and transfected groups. Therefore, we concluded that gene delivery by plasmid vector in association with ultrasound and hydrodynamics was highly effective in transfecting rat heart.