Salvagable free wall rupture of the left ventricle

Free wall rupture of the left ventricle remains a lethal complication of acute myocardial infarction. Nevertheless, where it presents subacutely with tamponade, salvage with a good outcome is still possible with timely pericardiocentesis preceding definitive repair using a sutureless technique.

Genotype spectrum of cervical human papillomavirus infection among sexually transmitted disease clinic patients in Hong Kong

Previous studies have suggested that a few uncommon human papillomavirus (HPV) genotypes are prevalent in Chinese cervical cancer patients. To elucidate the genotype spectrum of HPVs circulating among Hong Kong Chinese, a cross-sectional study was conducted on 553 women who attended a public sexually transmitted disease clinic. HPV DNA was detected from cervical samples using the polymerase chain reaction, followed by genotype identification based on restriction fragment length polymorphism and direct sequencing. The prevalence of HPV was 30.6% for all types combined, 14.8% for high-risk types, 10.8% for low-risk types, and 7.1% for unknown-risk types. Among the HPV-positive women, 89.9% had single type infections; whereas the other 10.1% harboured more than one HPV type. HPV11 was the most prevalent genotype, detected in 5.1% of subjects; followed by HPV16 (4.9%), HPV58 (4.3%), HPV6 (3.3%), and HPV53 and CP8304 (2.2% each). Other less common genotypes found were HPV18, 33, 39, 61, LVX160, MM4, MM7 (range: 0.7-1.6%); HPV26, 45, 54, 56, 59, and LVX100 (range: 0.4-0.5%); HPV35, 40, 52, 55, 68, MM8, and MM9 (0.2% each). This study shows that HPV58 is the second most common high-risk HPV genotype circulating among Chinese female sexually transmitted disease clinic patients in Hong Kong. This together with previous reports of the high prevalence of HPV58 among Chinese cervical cancer patients accentuate the importance of developing vaccines targeting at this otherwise uncommon genotype.

Clinical outcomes of patients with diabetes mellitus and acute myocardial infarction treated with primary angioplasty or fibrinolysis

OBJECTIVE

To compare the early and late outcomes of primary percutaneous transluminal coronary angioplasty (PTCA) with fibrinolytic treatment among diabetic patients with acute myocardial infarction (AMI).

DESIGN

Retrospective observational study with data obtained from prospective registries.

SETTING

Tertiary cardiovascular institution with 24 hour acute interventional facilities.

PATIENTS

202 consecutive diabetic patients with AMI receiving reperfusion treatment within six hours of symptom onset.

INTERVENTIONS

Fibrinolytic treatment was administered to 99 patients, and 103 patients underwent primary PTCA. Most patients undergoing PTCA received adjunctive stenting (94.2%) and glycoprotein IIb/IIIa inhibition (63.1%).

MAIN OUTCOME MEASURES

Death, non-fatal reinfarction, and target vessel revascularisation at 30 days and one year were assessed.

RESULTS

Baseline characteristics were similar in these two treatment groups except that the proportion of patients with Killip class III or IV was considerably higher in those treated with PTCA (15.5% v 6.1%, p = 0.03) and time to treatment was significantly longer (103.7 v 68.0 minutes, p < 0.001). Among those treated with PTCA, the rates for in-hospital recurrent ischaemia (5.8% v 17.2%, p = 0.011) and target vessel revascularisation at one year (19.4% v 36.4%, p = 0.007) were lower. Death or reinfarction at one year was also reduced among those treated with PTCA (17.5% v 31.3%, p = 0.02), with an adjusted relative risk of 0.29 (95% confidence interval 0.15 to 0.57) compared with fibrinolysis.

CONCLUSION

Among diabetic patients with AMI, primary PTCA was associated with reduced early and late adverse events compared with fibrinolytic treatment.

Cardiac output increases prior to development of pulmonary edema after re-expansion of spontaneous pneumothorax

Pulmonary edema following reexpansion of spontaneous pneumothorax is an uncommon complication. The underlying mechanism of this condition is unclear. We report the hemodynamic characteristics in a series of 7 male patients with spontaneous large (>50%) pneumothoraces of > or = 24 h and correlate the changes with reexpansion pulmonary edema (REPE). A pulmonary artery floatation catheter was inserted and hemodynamic data were obtained before therapeutic chest tube insertion, 1 h after chest tube insertion and the following day. Four (57%) patients developed REPE. There was a tendency for larger pneumothorax to develop REPE. Capillary wedge pressure did not change significantly 1 h after the insertion of chest tube in all our patients. Cardiac output increased significantly in patients who developed REPE compared to those who did not (+ 1.06 l/min vs -0.27 l/min; P = 0.03) 1 h after insertion of chest tube. One patient did not develop pulmonary edema despite having a large (> 80%) pneumothorax. His cardiac output did not rise 1 h after chest tube insertion. REPE is not an uncommon complication following chest tube drainage in patients with large and long-standing pneumothorax. The increase in cardiac output after chest tube insertion may be associated with subsequent development of REPE.

Gender differences in outcome after an acute myocardial infarction in Singapore

OBJECTIVES

To characterise gender and age-related differences in presentation and outcome after an acute myocardial infarction (AMI).

DESIGN

Data were derived retrospectively from the Singapore Myocardial Infarction Registry from 1988 through 1997. This database comprised all AMI cases for ages between 20 and 64 years (group A). For approximately three months a year, data were also collected for all AMI cases above the age of 64 years (group B). There were 13,048 and 4,425 cases in groups A and B respectively.

RESULTS

In age - standardised AMI rates, males outnumbered females by a factor of 4.0 and 1.7 for groups A and B respectively.The median age of presentation was higher in females for both age groups being 58 years versus 54 years for group A and 75 years versus 72 years for group B. Younger females had worse survival at 28 days and were more likely to have prior ischaemic heart disease and require resuscitation. They were also more likely to have atypical symptoms. Previous myocardial infarction was not different between the sexes in both groups. Among the older age group, there was no gender difference in prior ischaemic heart disease, 28-day survival and requirement for resuscitation.

CONCLUSION

Women who have AMI tend to be older than men. Gender differences are age-specific. Women who are 64 years and below have more atypical symptoms, prior ischaemic heart disease and worse prognosis than men after AMI. These differences are not seen in those over the age of 64.

Risk of influenza A (H5N1) infection among poultry workers, Hong Kong, 1997-1998

In 1997, outbreaks of highly pathogenic influenza A (H5N1) among poultry coincided with 18 documented human cases of H5N1 illness. Although exposure to live poultry was associated with human illness, no cases were documented among poultry workers (PWs). To evaluate the potential for avian-to-human transmission of H5N1, a cohort study was conducted among 293 Hong Kong government workers (GWs) who participated in a poultry culling operation and among 1525 PWs. Paired serum samples collected from GWs and single serum samples collected from PWs were considered to be anti-H5 antibody positive if they were positive by both microneutralization and Western blot testing. Among GWs, 3% were seropositive, and 1 seroconversion was documented. Among PWs, approximately 10% had anti-H5 antibody. More-intensive poultry exposure, such as butchering and exposure to ill poultry, was associated with having anti-H5 antibody. These findings suggest an increased risk for avian influenza infection from occupational exposure.

Coronary stenting in diabetic patients: Results from the ROSETTA registry

OBJECTIVE

Diabetes mellitus is associated with high rates of restenosis and adverse outcomes after percutaneous transluminal coronary angioplasty (PTCA). It is unclear whether coronary stenting reduces adverse events in diabetic patients after PTCA. Our purpose was to determine whether coronary stenting improves clinical event rates in diabetic patients after PTCA.

METHODS

The Routine Versus Selective Exercise Treadmill Testing After Angioplasty (ROSETTA) registry was a prospective multicenter observational study examining functional testing and adverse outcomes after successful PTCA.

RESULTS

Among the 791 patients enrolled, 180 were diabetic. A total of 90 diabetics received stents while the remaining 90 patients did not. Baseline clinical characteristics were similar between the 2 groups of patients. However, patients with stents were more likely to have complex lesions, whereas those without stents were more likely to undergo atherectomy and have greater residual coronary stenosis. At 6-month follow-up, the composite end point defined as cardiac death, unstable angina, myocardial infarction, need for repeat PTCA, or coronary artery bypass graft surgery (CABG) occurred in 25.0% of stented and 22.2% of nonstented diabetic patients (P not significant [NS]). A multivariate logistic regression analysis showed that coronary stenting was not associated with a reduced incidence of the composite end point among diabetic patients (odds ratio 0.97, 95% CI 0.46-2.05, P NS).

CONCLUSION

Coronary stenting does not improve clinical event rates in diabetic patients after PTCA.

Distally based sural neurocutaneous flaps for ankle and heel ulcers

This study assessed the use of sural neurocutaneous flaps to repair chronic ulcers in difficult-to-cover areas around the ankle and heel. Follow-up of the 14 patients included in this study ranged from 6 months to 3 years after their operation. Total flap loss occurred in two patients, both of whom had rheumatoid arthritis complicated by vasculitis. Partial flap loss occurred in three patients; all were heel ulcers. Additional skin grafting procedures were required to cover their ulcers. A lateral malleolus ulcer in a patient with rheumatoid arthritis recurred after 1 year and had to be covered with a free parascapular flap. The sural neurocutaneous flap is thus a reliable means of resurfacing ulcers in the ankle and heel region. It requires no sacrifice of major peripheral vessels and may be a useful alternative for patients with poor peripheral pulses. Its use in the presence of vasculitis, however, needs further refinement.

Mortality and smoking in Hong Kong: case-control study of all adult deaths in 1998

OBJECTIVE

To assess the mortality currently associated with smoking in Hong Kong, and, since cigarette consumption reached its peak 20 years earlier in Hong Kong than in mainland China, to predict mortality in China 20 years hence.

DESIGN

Case-control study. Past smoking habits of all Chinese adults in Hong Kong who died in 1998 (cases) were sought from those registering the death.

SETTING

All the death registries in Hong Kong.

PARTICIPANTS

27 507 dead cases (81% of all registered deaths) and 13 054 live controls aged >/=35 years.

MAIN OUTCOME MEASURES

Mortality from all causes and from specific causes.

RESULTS

In men aged 35-69 the adjusted risk ratios (and 95% confidence intervals) comparing smokers with non-smokers were 1.92 (1.70 to 2.16) for all deaths, 2.22 (1.94 to 2.55) for neoplastic deaths, 2.60 (2.10 to 3.21) for respiratory deaths (including tuberculosis, risk ratio 2.54), and 1.68 (1.43 to 1.97) for vascular deaths (each P<0.0001). In women aged 35-69 the corresponding risk ratios were 1.62 (1.40 to 1.88) for all deaths, 1.60 (1.33 to 1.93) for neoplastic deaths, 3.13 (2.21 to 4.44) for respiratory deaths, and 1.55 (1.20 to 1.99) for vascular deaths (each P<0.001). If these associations with smoking are largely or wholly causal then, among all registered deaths at ages 35-69 in 1998, tobacco caused about 33% (2534/7588) of all male deaths and 5% (169/3341) of all female deaths (hence 25% of all deaths at these ages). At older ages tobacco seemed to be the cause of 15% (3017/20 420) of all deaths.

CONCLUSIONS

Among middle aged men the proportion of deaths caused by smoking is more than twice as big in Hong Kong now (33%) as in mainland China 10 years earlier. This supports predictions of a large increase in tobacco attributable mortality in China as a whole.

Wear debris from total hip arthroplasty presenting as an intrapelvic mass

A granulomatous reaction to the small particles worn off from an implanted prosthesis is a common complication in arthroplasty. The chronic inflammatory response to the wear debris from either the polyethylene or the metal components is thought to be responsible for osteolysis, implant loosening, and finally mechanical failure. Formation of an extra-articular granulomatous tissue mass is uncommon, however. We report a case of a huge granulomatous mass that presented as an intrapelvic tumor. The prosthesis was an Anatomical Medullary Locking (AML) hip arthroplasty with cementless fixation. The polyethylene insert was manufactured by ram extrusion and sterilized with gamma irradiation in air. Fragments of the insert were among the contents in the cystic mass together with black metallic debris. There was no loosening of the prosthesis, and the acetabulum floor was preserved.

Lipodystrophia centrifugalis abdominalis infantilis: two cases from China

We report the first two Chinese patients with lipodystrophia centrifugalis abdominalis infantilis in China. The first patient was a 3-year-old girl who developed an area of hyperpigmented skin depression on the right groin which spread centrifugally to the abdomen and right lower chest. Later, another lesion developed on the neck. The second patient was a 4-year-old girl who developed multiple areas of skin depression on her bilateral groin, periumbilical region, right axilla, and chest. The lesions also extended centrifugally. Erythematous margins and lymphadenopathy were present in both cases. Inflammatory changes were found in the subcutaneous fat. The clinical pictures and histologic features supported the diagnosis of LCAI in both cases.

Use of routine functional testing after percutaneous transluminal coronary angioplasty: results from the ROSETTA Registry

BACKGROUND

The American College of Cardiology (ACC)/American Heart Association (AHA) guidelines for exercise testing suggest that only selected groups of high-risk patients should undergo routine functional testing after percutaneous transluminal coronary angioplasty (PTCA) for the detection of restenosis.

OBJECTIVES

Our purpose was (1) to document the patterns of use of post-PTCA functional testing and (2) to determine whether the choice of functional testing strategy is related to clinical characteristics of patients or whether physicians use a similar strategy for all their patients.

METHODS

The Routine Versus Selective Exercise Treadmill Testing After Angioplasty (ROSETTA) Registry is a prospective study examining the use of functional testing among 788 patients at 13 centers in 5 countries.

RESULTS

During the 6-month period after a successful PTCA, 49% of patients underwent functional testing (range among centers 10%-81%). Among patients who underwent functional testing, 39% had a clinical indication and 61% had functional testing as a routine follow-up. The first functional test was performed a median of 7 weeks after PTCA, with 13% of patients having second tests at a median of 14 weeks and 4% having additional tests at a median of 20 weeks. Univariate and multivariate analyses demonstrated that the chief determinant of the use of routine functional testing was clinical center. Aside from age (P <.0001), no baseline clinical or procedural characteristics were consistently associated with the use of routine functional testing after PTCA.

CONCLUSIONS

Physicians do not appear to be adhering to the ACC/AHA guidelines for exercise testing regarding the routine use of post-PTCA functional testing. None of the clinical characteristics identified by the ACC/AHA guidelines were associated with the routine use of post-PTCA functional testing, and the primary determinant of functional testing was the location of the center at which the patient had the PTCA.

Hierarchy of risk based on history and location of prior myocardial infarction in the thrombolytic era. GUSTO-I Investigators

BACKGROUND

Among patients receiving thrombolytic therapy for myocardial infarction, the outcome for those with a history of infarction is dramatically worse than for those with their first event. Methods And Results We performed a post hoc analysis of patients with a history of myocardial infarction enrolled in the Global Utilization of Streptokinase and TPA for Occluded arteries (GUSTO)-I trial, focusing on the impact of the location of their current and prior events on mortality rates. Within the first 24 hours, mortality rate was greatest among patients with a current infarction in a territory remote from their previous event. By 48 hours after examination, mortality rates among patients with a second anterior infarct had overtaken that among patients with a current inferior/prior anterior infarct. This hierarchy of risk persisted at both 30 days and 1 year (mortality rate at 1 year: current anterior/prior inferior 23.2% +/- 1.4%, current anterior/prior anterior 20% +/- 1.5%, current inferior/prior anterior 17% +/- 1.2%, current inferior/prior inferior 10.8% +/- 0. 9%).

CONCLUSIONS

In patients with ST-elevation myocardial infarction on a background of prior infarction, the location of current and prior events predicts a hierarchy of short- and long-term risk of death.

Emerging concepts in the management of acute myocardial infarction in patients with diabetes mellitus

Although fibrinolysis has improved survival of patients after myocardial infarction (MI), such therapy is less likely to be administered to patients with diabetes. Furthermore, these patients present later (15 min) than nondiabetics. Moreover, even with the use of early potent fibrinolytic agents, patients with diabetes continued to suffer excessive morbidity and mortality. This finding is not related to the ability of fibrinolytic agents to restore complete reperfusion or increased risk of reocclusion of the infarct-related artery. Instead, the impaired ventricular performance at the noninfarct areas and metabolic derangements during the acute phase of MI may account for the adverse outcome. The efficacy of percutaneous coronary revascularization procedures for treatment of acute MI requires further evaluation. Therapeutic approaches should consider correcting these abnormalities to afford greater survival benefit for this subset of high-risk patients.

Platelet glycoprotein IIb/IIIa receptor antagonists and their use in elderly patients

With increasing age of the general population, cardiovascular diseases are becoming a greater health burden. Coronary artery disease remains a major cause of morbidity and mortality worldwide. Among the various pathophysiological processes, platelets play a pre-eminent role. With the identification of the glycoprotein (GP) IIb/IIIa receptor as the final common pathway for platelet aggregation, potent antiplatelet agents have been developed. These GP IIb/IIIa antagonists have been shown to be effective in improving outcomes among patients undergoing percutaneous coronary interventions and for the treatment of acute coronary syndromes. By pooling the results of several large-scale trials, these benefits have been found to extend to the elderly population. Among 7860 patients undergoing percutaneous coronary intervention, the occurrence of death or myocardial infarction at 30 days was reduced from 10.0 to 5.9% (odds ratio 0.56; 95% confidence level, 0.37 to 0.83) with abciximab compared with placebo, in those >70 years of age. Importantly, this benefit was achieved without an increase in major bleeding complications. Similarly favourable trends were also observed among elderly patients treated with tirofiban or eptifibatide for acute coronary syndromes. As such, GP IIb/IIIa antagonists are effective in preventing ischaemic complications and can be safely administered to elderly patients.

Risk of influenza A (H5N1) infection among health care workers exposed to patients with influenza A (H5N1), Hong Kong

The first outbreak of avian influenza A (H5N1) occurred among humans in Hong Kong in 1997. To estimate the risk of person-to-person transmission, a retrospective cohort study was conducted to compare the prevalence of H5N1 antibody among health care workers (HCWs) exposed to H5N1 case-patients with the prevalence among nonexposed HCWs. Information on H5N1 case-patient and poultry exposures and blood samples for H5N1-specific antibody testing were collected. Eight (3.7%) of 217 exposed and 2 (0.7%) of 309 nonexposed HCWs were H5N1 seropositive (P=.01). The difference remained significant after controlling for poultry exposure (P=.01). This study presents the first epidemiologic evidence that H5N1 viruses were transmitted from patients to HCWs. Human-to-human transmission of avian influenza may increase the chances for the emergence of a novel influenza virus with pandemic potential.

Cost-efficacy modeling of functional testing with perfusion imaging to detect asymptomatic restenosis following percutaneous transluminal coronary angioplasty

The objective of this study was to perform a theoretical cost-efficacy analysis on the use of routine functional testing with perfusion imaging to identify patients with asymptomatic restenosis following percutaneous transluminal coronary angioplasty (PTCA) procedures. Approximately 50% of patients with restenosis following PTCA are asymptomatic. Routine functional testing is commonly performed at 3 to 6 months to identify these patients. The cost-efficacy associated with this strategy is unknown. Theoretical models were constructed based on assumed costs for functional testing (U.S. $1,300) and coronary angiography (U.S. $3,000). Restenosis rates were assumed to be 40%, and half of patients with restenosis were assumed to be asymptomatic. To provide a range of costs to identify a patient with asymptomatic restenosis, three scenarios were constructed based on the diagnostic test characteristics of functional testing. Sensitivity analyses were performed using a range of costs for functional testing, restenosis rates, and proportion of patients with restenosis who are asymptomatic. Depending on the diagnostic accuracy of functional testing, it costs $8,200 to $22,400 to identify an asymptomatic patient with restenosis following PTCA. The cost to identify a patient with asymptomatic restenosis varies inversely with the rates of restenosis. When restenosis rates are < 20%, the cost to identify a patient with asymptomatic restenosis exceeds $10,000. Similarly, the cost to identify a patient with asymptomatic restenosis increases when the proportion of patients with asymptomatic restenosis decreases. The cost, associated with the use of routine functional testing for the identification of asymptomatic patients with restenosis appears exorbitant. However, a formal study is warranted to determine the cost-efficacy of such a strategy. Cathet. Cardiovasc. Intervent. 48:352-356, 1999.

Antibody response in individuals infected with avian influenza A (H5N1) viruses and detection of anti-H5 antibody among household and social contacts

The first documented outbreak of human respiratory disease caused by avian influenza A (H5N1) viruses occurred in Hong Kong in 1997. The kinetics of the antibody response to the avian virus in H5N1-infected persons was similar to that of a primary response to human influenza A viruses; serum neutralizing antibody was detected, in general, >/=14 days after symptom onset. Cohort studies were conducted to assess the risk of human-to-human transmission of the virus. By use of a combination of serologic assays, 6 of 51 household contacts, 1 of 26 tour group members, and none of 47 coworkers exposed to H5N1-infected persons were positive for H5 antibody. One H5 antibody-positive household contact, with no history of poultry exposure, provided evidence that human-to-human transmission of the avian virus may have occurred through close physical contact with H5N1-infected patients. In contrast, social exposure to case patients was not associated with H5N1 infection.

Platelet glycoprotein IIb/IIIa inhibition in acute coronary syndromes

Acute coronary syndromes are a leading cause of hospitalization in industrialized countries. Current antithrombotic therapy focuses on relatively weak antiplatelet agents and heparin. The advent of inhibitors of the platelet glycoprotein IIb/IIIa receptor, the final common pathway for aggregation, provides a new therapeutic modality. Clinical trials with a total of more than 18,000 patients have clearly shown the benefits of intravenous IIb/IIIa blockade. Overall, at 30 days, 13 fewer deaths or myocardial infarctions occurred for every 1000 patients treated in these trials. This favorable outcome was extended to 6 months, resulting in 16 fewer such events per 1000 patients treated. Importantly, these benefits were not accompanied by an excessive occurrence in bleeding complications or thrombocytopenia. To further improve outcomes in this high-risk group of patients, strategies pertaining to prolonged periods of vessel passivation with oral formulations and early or delayed invasive approaches are being studied.

Diabetes mellitus: biological determinants of atherosclerosis and restenosis

Diabetes mellitus is a potent risk factor for the development of atherosclerosis. Patients with diabetes account for approximately 20% of patients presenting with acute coronary syndromes or for percutaneous coronary intervention. Furthermore, the incidence of diabetes continues to increase world-wide, such that substantial medical resources are allocated for the care of patients with diabetic cardiovascular complications. Although great strides have been made in reducing cardiovascular events in recent years, there has been little improvement in outcomes for patients with diabetes mellitus. This review will focus in the underlying patho-biology and the current status of therapeutic interventional strategies for patients with diabetes mellitus.

Case-control study of risk factors for avian influenza A (H5N1) disease, Hong Kong, 1997

In May 1997, a 3-year-old boy in Hong Kong died of a respiratory illness related to influenza A (H5N1) virus infection, the first known human case of disease from this virus. An additional 17 cases followed in November and December. A case-control study of 15 of these patients hospitalized for influenza A (H5N1) disease was conducted using controls matched by age, sex, and neighborhood to determine risk factors for disease. Exposure to live poultry (by visiting either a retail poultry stall or a market selling live poultry) in the week before illness began was significantly associated with H5N1 disease (64% of cases vs. 29% of controls, odds ratio, 4.5, P=.045). By contrast, travel, eating or preparing poultry products, recent exposure to persons with respiratory illness, including persons with known influenza A (H5N1) infection, were not associated with H5N1 disease.

Trends in mortality, incidence, hospitalisation, cardiac procedures and outcomes of care for coronary heart disease in Singapore, 1991-1996

In this study, we used Singapore population-based data from 1991 to 1996 to examine recent trends in mortality, incidence and hospitalisation for acute myocardial infarction (AMI), and explored the roles of primary prevention and medical care interventions in explaining these trends. We examined trends in medical interventions, namely coronary angiography (catheterisation), coronary artery bypass graft (CABG), and percutaneous transluminal coronary angioplasty (PTCA), length of stay, and payment methods, and explored the roles of technological, healthcare financing and delivery, and regulatory factors in influencing the diffusion and outcomes of these medical interventions. During the period 1991 to 1996, there were parallel declines in resident population rates of mortality, incidence and hospitalisation for AMI. The rates of angiograms, CABG and PTCA among residents also increased greatly, with the greatest increase among elderly aged 60 years and above. The rates of invasive cardiac procedures for AMI were all lower in females than in males. The population case-fatality rate of AMI declined slightly only for persons below 40 years of age. The case-fatality rate was higher in females than in males. The number of hospitalisations and cardiac procedures all rose sharply, and was phenomenal for PTCA (247%). The increase in volume of resource use was starkly greater in private hospitals than in restructured hospitals. The ratios of PTCA to CABG from 1991 to 1996 for private and restructured hospitals showed a greater rate of technology substitution in restructured hospitals than in private hospitals. The average length of stay (LOS, 6.7 days) was fairly constant in restructured hospitals. For private hospitals, LOS declined from 7.6 days in 1991 to 5.6 in 1996. LOS varied little among individual restructured hospitals, but widely among private hospitals. The most common method of payment for AMI hospitalisation was Medisave alone (50%), but for CABG surgery, the proportion of payment made through this method was only 12%. Out-of-pocket payments, Medisave, Medishield and private insurance have increased steadily. These data indirectly suggest that primary prevention and medical care interventions might have begun to succeed in reducing the rates of coronary heart disease in Singapore. The sharp increases in cardiac procedures may be explained by changing supply and demand factors for care of AMI and chronic ischaemic heart disease, including consumer preference for cardiac procedures, overuse of medical intervention, and technological change. More studies are needed to test these hypotheses.