Heart failure cohort in Singapore with defined criteria: clinical characteristics and prognosis in a multi-ethnic hospital-based cohort in Singapore.

INTRODUCTION: There are limited data on heart failure (HF) cohorts with objective clinical definition of HF. Many observational HF studies were based on discharge diagnosis codes, making them subjective. Many did not have contemporaneous left ventricular function assessment. This study was done to evaluate the characteristics and one-year prognosis of a single centre multi-ethnic Asian inpatient HF cohort, with these limitations addressed, with the aim of yielding a more accurate picture of true HF. METHODS: This was an observational prospective study. Patients who fulfilled the modified Framingham criteria for clinical HF and study inclusion criteria of serum creatinine level less than 267 micromol/L, serum albumin level greater than 28 g/L, and a contemporaneous trans-thoracic echocardiography (TTE) study were enrolled. TTE studies ordered were attempted within 72 hours. RESULTS: 173 patients were enrolled into the study. TTE was done within 72 hours of admission for 86.1 percent (n = 149) of the participants. Diastolic HF constituted 22.0 percent of the cohort. The mean age of the participants was 68.7 (standard deviation, 12.0) years. The prevalence of elderly patients, diabetes mellitus, hypertension and ischaemic cardiomyopathy were high. The one-year mortality rate was 20.8 percent (n = 36). The one-year death or readmission for any cause rate was 69.4 percent (n = 120). The mean time in hospital for any cause within the one year was 11.8 +/- 17.9 days. Ethnicity had prognostic implications. Being elderly, having elevated random blood glucose or serum creatinine levels were associated with a worse prognosis. CONCLUSION: With strict methodology, HF is truly a disease of the elderly, with significant one-year mortality and morbidity consequences. Prognostic characteristics are reviewed.

The role of spiral computed tomogram in the diagnosis of acute pulmonary embolism.

Acute pulmonary embolism is associated with considerable morbidity and mortality. Early diagnosis and prompt treatment is essential. A number of non-invasive diagnostic tools are available for its detection. However, each one of these tests has its limitations and the invasive pulmonary angiography remains the gold standard. We describe the use of spiral volumetric computerised tomogram in the diagnosis of acute pulmonary embolism in six patients in our centre where ventilation-perfusion scan facility is not available. This safe, simple and non-invasive test has an excellent sensitivity and specificity for the detection of central and segmental pulmonary embolism and may replace the conventional invasive pulmonary angiography for the diagnosis of pulmonary embolism.

Intracoronary brachytherapy: the beginning of the end of restenosis?

Restenosis remains a major problem 20 years after the introduction of coronary angioplasty. Pharmacological therapy has generally been disappointing in reducing the incidence of neointimal hyperplasia. Intracoronary brachytherapy is the latest anti proliferative agent that is showing promise in the fight against restenosis. Radiation therapy has been used for decades in the treatment of benign proliferative disorders. Animal studies have consistently demonstrated the efficacy of radiation therapy in inhibiting neointimal hyperplasia. Clinical trials, using different radioactive isotopes and radiation sources, are now showing dramatic reduction in neointimal hyperplasia and restenosis rates following balloon angioplasty and stenting. Intracoronary brachytherapy is beginning to show promise as one of the truly effective agent against neointimal hyperplasia and restenosis.

Immediate and long-term effect of mitral balloon valvotomy on left ventricular volume and systolic function in severe mitral stenosis.

To determine the immediate and long-term effect of mitral balloon valvotomy (MBV) on left ventricular (LV) volume and function, we studied 17 patients (mean age 27 +/- 9 years) with severe mitral stenosis undergoing MBV by cardiac catheterization and angiography before and immediately after MBV and at mean 12 months later. At baseline, LV end-diastolic volume index (EDVI) was reduced. Ten patients had EDVI < or = 55 ml/m2, and four patients (23.5%) had LV ejection fraction < 50%. EDVI increased from 60 +/- 17 ml/m2 to 66 +/- 17 ml/m2 (p < 0.05) immediately after MBV and increased further to 72 +/- 16 ml/m2 (p < 0.05) later. Stroke volume index increased from 34 +/- 10 ml/m2 to 41 +/- 12 ml/m2 (p < 0.05) immediately after MBV and increased further to 50 +/- 11 ml/m2 (p < 0.001) later. LV end diastolic pressure increased from 12 +/- 5 mm HG to 16 +/- 4 mm HG (p < 0.05) immediately after MBV and fell to 13 +/- Hg at follow-up. LV ejection fraction increased from 57 +/- 7% to 62 +/- 6% (p < 0.05) immediately after MBV and 71 +/- 8% later (p < 0.001). Mean systolic ejection rate increased from 82 +/- 35 ml/sec to 101 +/- 48 ml/sec (p < 0.05) immediately after and 165 +/- 81 ml/sec later (p < 0.05). Systemic vascular resistance fell from 1887 +/- 525 dyne/sec/cm-5 to 1280 +/- 231 dyne/sec/cm-5 (p < 0.001) at follow-up. We conclude that the LV end-diastolic volume and systolic function are reduced in patients with mitral stenosis, and the LV end-diastolic volume is increased immediately after MBV and continues to increase at follow-up 12 months later; the LV ejection performance improves after successful MBV because of an increase in end-diastolic LV volume (preload) and reduction of SVR.

Interobserver and intraobserver variation for analysis of left ventricular wall motion at baseline and during low- and high-dose dobutamine stress echocardiography in patients with high prevalence of wall motion abnormalities at rest.

Interobserver and intraobserver variation for analysis of left ventricular regional wall motion during dobutamine stress echocardiography was assessed. Computer-displayed cineloops from 33 patients, 25 with baseline wall motion abnormalities, were analyzed by two observers blinded for patient data. Assessment included (1) baseline wall motion abnormalities, (2) evidence of myocardial viability at 10 micrograms/kg/min dobutamine, and (3) evidence of myocardial ischemia at 30 to 40 micrograms/kg/min. Wall motion score index was calculated at each stage. Interobserver and intraobserver agreement for baseline wall motion abnormalities was 100%. Interobserver agreement for viability and ischemia was 84% and 82%, respectively; intraobserver agreement was 92% and 85%, respectively. Mean interobserver differences in wall motion score index ranged from 0.06 +/- 0.14 at baseline to 0.09 +/- 0.20 at high doses (p < 0.05 at all levels); mean intraobserver differences ranged from 0.001 +/- 0.14 to 0.01 +/- 0.15 (difference not significant at all levels).

Advantage of Inoue balloon catheter in mitral balloon valvotomy: experience with 220 consecutive patients.

Percutaneous mitral balloon valvotomy (PMV) using the Inoue balloon catheter was attempted in 220 consecutive patients with severe symptomatic mitral stenosis. Their age range was 10-63 mean 30 +/- 10 years; 161 patients were females and 59 were males; 29 patients were in atrial fibrillation. Eleven patients were pregnant; 14 patients underwent previous surgical commissurotomy. The procedure was technically successfully performed in 215 (97.7%) patients. The mean fluoroscopy time was 15.5 +/- 6.4 min and mean procedure time was 109 +/- 79 min. Optimal results (group I) was achieved in 207 patients who have mitral score of 7 +/- 1. PMV resulted in decrease in left atrial pressure from 23 +/- 5 to 14 +/- 4 mm Hg (P < 0.001), the mean mitral valve gradient (MVG) decreased from 15 +/- 4 to 6 +/- 3 mm Hg (P < 0.001). The mitral valve area (MVA) by catheter increased from 0.7 +/- 0.2 to 1.7 +/- 0.5 cm2 (P < 0.001) and MVA as determined by echocardiography (2DE) increased from 0.8 +/- 0.1 to 1.9 +/- 0.3 cm2 (P < 0.001). The results were suboptimal in eight patients who have a mitral score of 10 +/- 1 (group II) MVA by catheter increased from 0.7 +/- 0.2 to 1 +/- 0.1 cm2 and Doppler MVA increased from 0.8 +/- 0.1 to 1.3 +/- 0.1 cm2. There were no deaths or thromboembolism. Two patients developed cardiac tamponade; mild mitral regurgitation (MR) developed in 24 patients (11%) and increased by one grade in another 22 patients (10%). Severe MR was encountered in three patients (1.4%). A small ASD (QP/QS < or = 1.3) was detected by oximetry in 5% of patients and by color-flow mapping in 26% of patients. One hundred fifty-eight patients from group I were followed up, for a mean of 32 +/- 12 months; MVA remained at 1.7 +/- 0.4 cm2. Seven patients developed mitral restenosis in group I, and 5 out of 8 patients developed restenosis in group II. We conclude that the hemodynamic results are good and comparable with those reported with double balloon technique. However, the Inoue balloon has several advantages over the double balloon technique: (1) low incidence of mitral regurgitation and ASDs; (2) shorter procedure and fluoroscopy time; and (3) low complication rates and the valve anatomy affects the immediate and late outcome of mitral balloon valvotomy.

Immediate and long-term effect of mitral balloon valvotomy on severe pulmonary hypertension in patients with mitral stenosis.

The pulmonary vascular hemodynamics were studied in 21 patients with severe mitral stenosis and severe pulmonary hypertension. Hemodynamic data were obtained before and immediately after mitral balloon valvotomy (MBV) and at follow-up 7 to 14 months (mean 12 months) later by repeat catheterization. The mean pulmonary capillary wedge pressure (PCW) decreased from 27 +/- 5 to 15 +/- 4 mm Hg (p < 0.001). The mean mitral valve gradient (MVG) decreased from 18 +/- 4 to 6 +/- 2 mm Hg (p < 0.001). Mitral valve area (MVA) increased from 0.6 +/- 0.1 to 1.5 +/- 0.3 cm2 (p < 0.02). Cardiac index increased from 2.2 +/- 0.3 to 2.6 to 0.5 L/min/m2 (p < 0.02). The pulmonary artery systolic pressure decreased from 65 +/- 13 to 50 +/- 13 mm Hg (p < 0.001), and no significant change was seen in pulmonary vascular resistance (PVR) immediately after MBV from 461 +/- 149 to 401 +/- 227 dynes/sec/cm(-5) (p = 0.02). At follow-up the MVA increased from 1.5 +/- 0.3 to 1.7 +/- 0.3 cm2 (p < 0.02). Cardiac index increased further to 3 +/- 0.4 L/min/m2 (p < 0.02). MVG and PCW pressure remained the same. The pulmonary artery systolic pressure decreased further to 38 +/- 9 mm Hg (p < 0.02). PVR decreased significantly to 212 +/- 99 dynes/sec/cm(-5) (p < 0.02). We concluded that the pulmonary artery pressure decreased without normalizing immediately after MBV and normalized in patients with optimal results from mitral balloon valvotomy 7 to 14 months later. Insignificant change in PVR was seen immediately after MBV and markedly decreased or normalized at late follow-up in patients with optimal result from MBV.