Shih-Kai Lin

Comparing culprit lesions in ST-segment elevation and non-ST-segment elevation acute coronary syndrome with 64-slice multidetector computed tomography

BACKGROUNDnClassifying acute coronary syndrome (ACS) as ST elevation ACS (STE-ACS) or non-ST elevation ACS (NSTE-ACS) is critical for clinical prognosis and therapeutic decision-making. Assessing the differences in composition and configuration of culprit lesions between STE-ACS and NSTE-ACS can clarify their pathophysiologic differences.nnnOBJECTIVEnThis study focused on evaluating the ability of 64-slice multidetector computed tomography (MDCT) to investigate these differences in culprit lesions in patients with STE-ACS and NSTE-ACS.nnnMETHODSnOf 161 ACS cases admitted, 120 who fit study criteria underwent MDCT and conventional coronary angiography. The following MDCT data were analyzed: calcium volume, Agatston calcium scores, plaque area, plaque burden, remodeling index, and plaque density.nnnRESULTSnThe MDCT angiography had a good correlation with conventional coronary angiography regarding the stenotic severity of culprit lesions (r=0.86, p<0.001). The STE-ACS culprit lesions (n=54) had significantly higher luminal area stenosis (78.6+/-21.2% vs. 66.7+/-23.9%, p=0.006), larger plaque burden (0.91+/-0.10 vs. 0.84+/-0.12, p=0.007) and remodeling index (1.28+/-0.34 vs. 1.16+/-0.22, p=0.021) than those with NSTE-ACS (n=66). The percentage of expanding remodeling index (remodeling index >1.05) was significantly higher in the STE-ACS group (81.5% vs. 63.6%, p=0.031). The patients with STE-ACS had significantly lower MDCT density of culprit lesions than patients with NSTE-ACS (25.8+/-13.9HU vs. 43.5+/-19.1HU, p<0.001).nnnCONCLUSIONSnSixty-four-slice MDCT can accurately evaluate the stenotic severity and composition of culprit lesions in selected patients with either STE-ACS or NSTE-ACS. Culprit lesions in NSTE-ACS patients had significantly lower luminal area stenosis, plaque burden, remodeling index and higher MDCT density, which possibly reflect differences in the composition of vulnerable culprit plaques and thrombi.

Major Events in Uremic Patients: Insight from Parameters Derived by Flow Propagation Velocity

BACKGROUNDnThe parameters derived by flow propagation velocity (FPV) of early-diastolic mitral inflow have been proved to be associated with cardiovascular risk. This study was undertaken to analyze the prognosis of uremic patients by FPV.nnnMETHODSnA total of 100 uremic patients were enrolled. All patients underwent conventional echocardiographic examination and FPV measurement. Those examinations were performed before and after hemodialysis (within 30 minutes). Patients were followed for 4 years. Major events were recorded and defined as any-cause mortality and nonfatal cardiovascular events with hospitalization. Patients were separated into two groups according to a post-dialytic E/FPV of <1.5 or > or =1.5 (early-diastolic velocity of mitral inflow divided by FPV).nnnRESULTSnTwenty-six major events were recorded, including 13 cases with mortality and 13 cases with nonfatal cardiovascular events. The patients with a post-dialytic E/FPV of > or =1.5 had a higher prevalence of underlying coronary arterial disease (30% vs. 17%), left ventricular systolic dysfunction (left ventricular ejection fraction: 46% +/- 10% vs. 52% +/- 8%), and a major event. By Cox regression analysis, a post-dialytic E/FPV of > or =1.5 (hazard ratio 2.358, 95% confidence interval 1.118-4.62, P = .008) was the strongest independent factor to predict the major events, after adjustment of other covariates.nnnCONCLUSIONnA post-dialytic E/FPV of > or =1.5 predicts higher adverse events in uremic patients.

Role of Shortened QTc Dispersion in In-hospital Cardiac Events in Patients Undergoing Percutaneous Coronary Intervention for Acute Coronary Syndrome

Background: QT dispersion (QTD) refers to the difference between maximal and minimal QT values on the electrocardiogram (ECG). QTD values are calculated and corrected with Bazetts formula (corrected QTD = QTcD = QTD/vRR). QTcD increases in patients with acute coronary syndrome (ACS). Recovery of increased QTcD (shortened QTcD) develops after successful revascularization, but prolonged QTcD occurs in certain patients. The aim of this study is to ascertain the clinical significance between shortened and prolonged QTcD groups after percutaneous coronary intervention (PCI). Methods: We retrospectively enrolled 128 patients with ACS who had received PCI. The values of QTcD were measured manually on 12‐lead standard ECGs obtained within 3 days before and after PCI (pre‐PCI QTcD and post‐PCI QTcD). All the patients were divided into 2 groups. The shortened QTcD group was defined as those patients with a decrease in QTcD after PCI and the prolonged QTcD group as those with an increase in QTcD after PCI. The underlying diseases, various clinical classifications and some prognostic factors were taken into comparison and statistical analysis between these 2 groups. Results: The shortened QTcD group showed a significantly higher rate of in‐hospital cardiac death (13% vs. 0%, p = 0.006) and a greater pre‐PCI QTcD (100.8 ± 39.5 vs. 61.3 ± 24.1 ms, p < 0.001) than the prolonged QTcD group. There was a significantly greater pre‐PCI QTcD in patients with cardiac death than those without cardiac death (111.6 ± 38.3 vs. 83.3 ± 38.3 ms, p = 0.027). Furthermore, the patients with in‐hospital cardiac death presented with a significantly more frequent occurrence of in‐hospital ventricular arrhythmia, compared with those without cardiac death (30.0% vs. 4.0%, p = 0.014). Conclusion: Among the patients with ACS undergoing PCI, directly divided into shortened and prolonged QTcD groups regardless of initial pre‐PCI QTcD, the shortened QTcD group showed a higher occurrence of in‐hospital cardiac death and a greater pre‐PCI QTcD. Shortened QTcD might be 1 risk factor for in‐hospital cardiac death.

Tricuspid flow propagation velocity predicts exercise tolerance and readmission in patients with systemic lupus erythematosus.

BACKGROUNDnEvaluating right ventricular dysfunction, pulmonary artery systolic pressure (PASP), and exercise tolerance is critical in patients with systemic lupus erythematosus (SLE) because of the high mortality rate in such patients with pulmonary arterial hypertension (PAH). The aim of this study was to use the flow propagation velocity (FPV) of early diastolic tricuspid inflow to evaluate exercise tolerance and PAH severity and to predict readmission in patients with SLE.nnnMETHODSnA total of 66 patients with SLE with or without PAH and 30 healthy control subjects were enrolled. Controls were age-matched to patients with SLE and without PAH. All patients completed the 6-minute walking distance (6MWD) test and underwent standard echocardiography. Tricuspid FPV was measured in the modified parasternal short-axis view using the color M-mode technique. PAH was defined as PASP > 35 mm Hg using the tricuspid regurgitant method.nnnRESULTSnPatients with SLE and PAH had significantly lower tricuspid FPVs and 6MWDs than patients in the other 2 groups (both P values < .001). Tricuspid FPV was well correlated with 6MWD (r = 0.748, P < .001). In multivariate analysis, right atrial pressure was the only independent factor affecting tricuspid FPV (R(2) = 0.394, P < .001), and 6MWD was affected only by tricuspid FPV and PASP (R(2) = 0.629, P < .001). Patients with SLE who had been readmitted had lower tricuspid FPVs than those who had not (P = .035). Furthermore, FPV > or = 35.4 cm/s predicted 6MWD > or = 350 m and a lower 1-year readmission rate with good sensitivity and specificity.nnnCONCLUSIONnThe tricuspid FPV technique provides a simple method for predicting exercise tolerance, the severity of PAH, and readmission among patients with SLE.

Utility of Left Atrial Expansion Index and Stroke Volume in Management of Chronic Systolic Heart Failure

Background Titration of evidence‐based medications, important for treating heart failure (HF), is often underdosed by symptom‐guided treatment. The aim of this study was to investigate, using echocardiographic parameters, stroke volume and left ventricular (LV) filling pressure to guide up‐titration of medications, increasing prognostic benefits. Methods A total of 765 patients with chronic HF and severely reduced LV ejection fractions (<35%), referred from 2008 to 2016, were prospectively studied. Echocardiographic guidance was performed in 149 patients. LV filling pressure was assessed by left atrial expansion index, and stroke volume was estimated from diameter and time‐velocity integral in the LV outflow tract. Up‐titration of evidence‐based medications and adjustment for side effects or worsening clinical conditions according to those parameters were performed. Propensity score matching was used to match pairs of patients with (n = 110) or without (n = 110) echocardiographic guidance. End points were 4‐year frequencies of HF hospitalization and all‐cause mortality. Results During a mean follow‐up time of 4.1 years, rates of adverse events were 58 (52.7%) with no echocardiographic guidance and 36 (32.7%) with echocardiographic guidance (P < .0001). Echocardiography provided effective guidance to reduce prescribing frequency and dose of diuretics and to promote evidence‐based medication prescription. It reduced HF rehospitalization and all‐cause mortality. By multivariate analysis, prognostic improvement was associated with up‐titration of medications with echocardiographic guidance. Conclusions There was a statistically significant difference in long‐term prognosis between propensity score–matched pairs of patients with chronic severe HF with and without echocardiographic guidance. These findings need further validation in large prospective clinical trials. HighlightsLA expansion index and stroke volume were utilized in management of chronic systolic HF.The rate of adverse events was lower in echocardiographic guidance (32.7% vs 52.7%).This strategy can reduce the prescribing frequency and dose of diuretics.It can promote the maximal tolerable evidence‐based medication prescription.

P-35 Quality-of-Care Indicators in Patients with Acute Myocardial Infarction Can Be Improved by a Continuous Quality Improvement Program

DS rats exhibited LV hypertrophy at 11 weeks, and decreased systolic function at 18 weeks. LV mRNA levels of LOX-1 indicated a 4.7-fold increase in DS rats compared with control salt-resistant Dahl (DR) rats at 11 weeks, and a 32fold increase at 18 weeks. Immunohistochemistry revealed that LOX-1 expression in vessel walls and cardiomyocytes were greater in DS than DR rat hearts. The mRNA levels of LOX-1 were significantly correlated with blood pressure, LV/body weight ratio, LV wall thickness, and LV end-systolic dimension, and strongly correlated with the decrease of ejection fraction (r = 0.772) and the increases of BNP levels on plasma (r = 0.744) and mRNA (r = 0.814). Importantly, the mRNA levels of LOX-1 revealed the strongest correlation with a chemotactic factor MCP-1 (r = 0.943), and proinflammatory cytokines TGF-b1 (r = 0.936) and IL-1b (r = 0.760). These findings demonstrate that LV expression of LOX-1 is markedly increased in DS rat model of hypertension and possibly involved in chronic inflammation during the development of heart failure.