Association between Coronary Artery Spasm and the risk of incident Diabetes: A Nationwide population-based Cohort Study

Background: Non-diabetic coronary artery spasm (CAS) without obstructive coronary artery disease increases insulin resistance. We investigated the risk of incident type 2 diabetes (diabetes) associated with CAS. Methods: Patient records were retrospectively collected from the Taiwan National Health Insurance Research Database during the period 2000-2012. The matched cohorts consisted of 12,413 patients with CAS and 94,721 patients in the control group. Results: During the entire follow-up, the incidence of newly-diagnosed diabetes was 22.2 events per 1000 person-years in the CAS group and 13.9 events per 1000 person-years in the control group. The increased risk of CAS-related incident diabetes was observed regardless of sex and length of follow-up. The median time to incident diabetes was 2.9 and 3.5 years in the CAS and the control group (P <0.001), respectively, regardless of sex. Although age did not affect the risk of CAS-related incident diabetes, the risk was less apparent in the subgroups of male, dyslipidemia, chronic obstructive pulmonary disease, stroke, gout and medicated hypertension. However, CAS patients aged <50 years compared with patients ≥50 years had a greater risk of incident diabetes in females but not in males. Older CAS patients developed diabetes in a shorter length of time than younger patients. Conclusion: CAS is a risk factor for incident diabetes regardless of sex. However, females aged <50 years have a more apparent risk for CAS-related diabetes than old females, which is not observed in males. The median time of 2.9 years to incident diabetes warrants close follow-up.

Sodium-glucose cotransporter 2 inhibitor versus metformin as first-line therapy in patients with type 2 diabetes mellitus: a multi-institution database study

BACKGROUND

Sodium-glucose co-transporter 2 inhibitors (SGLT2i) has shown evidence of cardiovascular benefit in patients with type 2 diabetes mellitus (T2DM). Currently metformin is the guideline-recommended first-line treatment. We aimed to investigate the benefit of SGLT2i vs metformin as first-line therapy.

METHODS

Electronic medical records from Chang Gung Research Database during 2016-2019 were retrieved for patients with T2DM. Patients aged < 20, not receiving anti-diabetic medication, first-line treatment neither metformin nor SGLT2i were excluded. Primary outcomes were heart failure hospitalization, acute coronary syndrome, ischemic stroke, and all-cause mortality. Patients were followed up for events or December 31, 2019, whichever comes first.

RESULTS

After exclusion criteria, a total of 41,020 patients with T2DM were eligible for analysis. There were 1100 patients with SGLT2i as first-line and 39,920 patients with metformin as first-line treatment. IPTW was used for propensity score matching. During one year follow-up, the hazard ratio (HR) of patients on SGLT2i as first-line treatment to patients on metformin as first-line treatment were HR 0.47 (95% CI 0.41-0.54, p < 0.0001) in heart failure hospitalization, HR 0.50 (95% CI 0.41-0.61, p < 0.0001) in acute coronary syndrome, HR 1.21 (95% CI 1.10-1.32, p < 0.0001) in ischemic stroke, and HR 0.49 (95% CI 0.44-0.55, p < 0.0001) in all-cause mortality.

CONCLUSIONS

In patients with T2DM, SGLT2i as first-line treatment may be associated with decreased events of heart failure hospitalization, acute coronary syndrome, and all-cause mortality, compared with metformin as first-line treatment. However, there may be an increased events of ischemic stroke using SGLT2i compared to metformin.

Effects of National Hospital Accreditation in Acute Coronary Syndrome on In-Hospital Mortality and Clinical Outcomes

Background

Acute coronary syndrome (ACS) is a life-threatening medical condition that accounts for an annual expenditure of more than $300 billion in the United States. Hospital accreditation has been shown to improve patient and hospital outcomes for various conditions.

Objectives

This study aimed to determine the benefits of hospital accreditation in patients with ACS.

Methods

This nationwide population-based cohort study used Taiwan's National Health Insurance Research Database from 1997 to 2011 (n = 249,354). Multivariable logistic regression was used to analyze the risk of in-hospital events among those treated in accredited and non-accredited hospitals, and to compare outcomes in hospitals before and after accreditation. The effect of accreditation on these events was also stratified by accreditation grade.

Results

A total of 823 hospitals were included, of which 2.4% were medical centers, 13.7% were regional hospitals, and 83.8% were district hospitals. The in-hospital mortality [odds ratio (OR), 0.82; 95% confidence interval (CI), 0.79-0.85; p < 0.001] and recurrent acute myocardial infarction (AMI) admission (OR, 0.81; 95% CI, 0.71-0.93; p = 0.003) rates were significantly lower in the after-accreditation group than in the before-accreditation group. There was a substantial and marked decrease in the in-hospital mortality rate after accreditation in 2008.

Conclusions

This cohort study demonstrated that ACS accreditation was associated with better in-hospital mortality and recurrent AMI admission rates in ACS patients.

Clinical outcomes of second-generation limus-eluting stents compared to paclitaxel-eluting stents for acute myocardial infarction with cardiogenic shock

Objective

Whether the cardiovascular (CV) outcomes of second-generation limus-eluting stents (LESs) differ from those of paclitaxel-eluting stents (PESs) in patients with acute myocardial infarction (AMI) complicated by cardiogenic shock (CS) is still unclear.

Methods

We used the Taiwan National Health Insurance Research Database to analyse data of 516 patients with AMI and CS diagnosed from January 2007 to December 2011. We used propensity score matching to adjust for the imbalance in covariate baseline values between these two groups. We evaluated clinical outcomes by comparing 197 subjects who used second-generation LESs to 319 matched subjects who used PESs.

Results

The risk of the primary composite outcomes (i.e., myocardial infarction, coronary revascularisation or CV death) was significantly lower in the second-generation LES group than in the PES group [37.3% vs. 51.8%; hazard ratio (HR), 0.73; 95% CI: 0.56–0.95] at the 12-month follow-up. The patients who received second-generation LESs had a lower risk of coronary revascularisation (HR 0.62; 95% CI: 0.41–0.93) than those who used PESs. However, the risks of myocardial infarction (HR 0.56; 95% CI: 0.26–1.24), ischemic stroke (HR 0.73; 95% CI: 0.23–2.35), or CV death (HR 0.90; 95% CI: 0.63–1.28) were not significantly different between the two groups.

Conclusions

Among patients with CS-complicating AMI, second-generation LES implantation significantly reduced the risk of coronary revascularisation and composite CV events compared to PES implantation at the 12-month follow-up.

Cardiovascular risk of sitagliptin in ischemic stroke patients with type 2 diabetes and chronic kidney disease: A nationwide cohort study

Limited data are available about the cardiovascular (CV) safety and efficacy of sitagliptin, a dipeptidyl peptidase-4 (DPP-4) inhibitor, in ischemic stroke patients with type 2 diabetes mellitus (T2DM) and chronic kidney disease (CKD). Ischemic stroke patients with T2DM and CKD were selected from the Taiwan National Health Insurance Research Database (NHIRD) from March 1, 2009 to December 31, 2011. A total of 1375 patients were divided into 2 age- and gender-matched groups: patients who received sitagliptin (n = 275; 20%) and those who did not (n = 1,100). Primary major adverse cardiac and cerebrovascular events (MACCE), including ischemic stroke, hemorrhagic stroke, myocardial infarction (MI), or CV death, were evaluated. During a mean 1.07-year follow-up period, 45 patients (16.4%) in the sitagliptin group and 165 patients (15.0%) in the comparison group developed MACCEs (Hazard ratio [HR] 1.05; 95% confidence interval [CI], 0.75-1.45). Compared to the non-sitagliptin group, the sitagliptin group had a similar risk of ischemic stroke (HR 0.82; 95% CI, 0.51-1.32.), hemorrhagic stroke (HR 1.50; 95% CI, 0.58-3.82), MI (HR 1.14; 95% CI, 0.49-2.65), and CV mortality (HR 1.06; 95% CI, 0.61-1.85). The use of sitagliptin in recent ischemic stroke patients with T2DM and CKD was not associated with increased or decreased risk of adverse CV events.

Acute kidney injury in patients with pulmonary embolism: A population-based cohort study

Acute kidney injury (AKI) is overlooked in patients with pulmonary embolism (PE). Risk factors for and long-term outcomes of this complication remain unknown. This study evaluated the predictors and prognosis of AKI in patients with PE.This retrospective cohort study used Taiwan's National Health Insurance Research Database. We enrolled a total of 7588 patients who were admitted to a hospital for PE from January1997 to December 2011 and administered anticoagulation or thrombolytic agents. All demographic data, risk factors, and outcomes were analyzed.AKI was diagnosed in 372 (4.9%) patients. Multivariate logistic regression analysis revealed pre-existing chronic kidney disease, hypertension, diabetes mellitus, massive PE, anemia, and sepsis as independent risk factors for AKI. In the long-term follow-up, the survival rate was similar in the AKI and non-AKI groups.Careful risk factor screening and intensive intervention in patients with AKI might yield outcomes similar to those in patients without AKI.

Layer-specific quantification of myocardial deformation in sepsis-induced Takotsubo cardiomyopathy: Three case reports of a serial 2-dimensional speckle-tracking echocardiographic study

INTRODUCTION

Little is known about the time-course changes in left ventricular myocardial deformation in patients with Takotsubo cardiomyopathy (TC) using layer-specific quantification of myocardial deformation assessed by 2-dimensional speckle tracking echocardiography (2DSTE).

CASE SUMMARY

In this retrospective 2DSTE follow-up study of 3 female patients with sepsis-induced TC, we examined changes in strain among the 3 myocardial layers, and examined the changes in left ventricular diastolic function and right ventricular systolic function. In all 3 patients, there was improvement of at least 15% in left ventricular ejection fractions, and improvement in left ventricular longitudinal and circumferential strains. The absolute differences in left ventricular global strains between the endocardium and epicardium, and between the first and the third 2DSTE studies reflect the following: a decrease in all 3 myocardial layers in patients with acute TC; and a slower improvement in mid-myocardial and epicardial function during recovery of TC. In addition, the right ventricular free wall strains were also impaired in the acute stage of TC with gradual improvement during recovery.

CONCLUSIONS

Left ventricular strains did not fully recover even 1 month after acute TC. In addition, right ventricular free wall strains were also impaired in all 3 patients initially. In this case series, we found that layer-specific 2DSTE is a more sensitive method for myocardial function assessment than standard echocardiography.

Benefits of Intraaortic Balloon Support for Myocardial Infarction Patients in Severe Cardiogenic Shock Undergoing Coronary Revascularization

Background

Prior studies have suggested intraaortic balloon pump (IABP) have a neutral effect on acute myocardial infarction (AMI) patients with cardiogenic shock (CS). However, the effects of IABP on patients with severe CS remain unclear. We therefore investigated the benefits of IABP in AMI patients with severe CS undergoing coronary revascularization.

Methods and Results

This study identified 14,088 adult patients with AMI and severe CS undergoing coronary revascularization from Taiwan’s National Health Insurance Research Database between January 1, 1997 and December 31, 2011, dividing them into the IABP group (n = 7044) and the Nonusers group (n = 7044) after propensity score matching to equalize confounding variables. The primary outcomes included myocardial infarction(MI), cerebrovascular accidents or cardiovascular death. In-hospital events including dialysis, stroke, pneumonia and sepsis were secondary outcomes. Primary outcomes were worse in the IABP group than in the Nonusers group in 1 month (Hazard ratio (HR) = 1.97, 95% confidence interval (CI) = 1.84–2.12). The MI rate was higher in the IABP group (HR = 1.44, 95% CI = 1.16–1.79), and the cardiovascular death was much higher in the IABP group (HR = 2.07, 95% CI = 1.92–2.23). The IABP users had lower incidence of dialysis (8.5% and 9.5%, P = 0.04), stroke (2.6% and 3.8%, P<0.001), pneumonia (13.9% and 16.5%, P<0.001) and sepsis (13.2% and 16%, P<0.001) during hospitalization than Nonusers.

Conclusion

The use of IABP in patients with myocardial infarction and severe cardiogenic shock undergoing coronary revascularization did not improve the outcomes of recurrent myocardial infarction and cardiovascular death. However, it did reduce the incidence of dialysis, stroke, pneumonia and sepsis during hospitalization.

Clinical outcomes of drug-eluting stents versus bare-metal stents in patients with cardiogenic shock complicating acute myocardial infarction

BACKGROUND

To investigate the cardiovascular (CV) outcomes of drug-eluting stents (DESs) versus bare-metal stents (BMSs) in patients with acute myocardial infarction (AMI) complicated by cardiogenic shock (CS).

METHODS

Data from the Taiwan National Health Insurance Research Database was analyzed between January 1, 2007 and December 31, 2011. A total of 3051 AMI patients in CS were selected as the study cohort. Their clinical outcomes were evaluated by comparing 1017 subjects who used DESs to 2034 matched subjects who used BMSs.

RESULTS

The risk of the primary composite outcome (i.e., death, myocardial infarction, stroke, and coronary revascularization) was significantly lower in the DES group compared with the BMS group [56.1% vs. 66.2%, hazard ratio (HR), 0.74; 95% CI, 0.67-0.81] with a mean follow-up of 1.35years. The patients who received DESs had a lower risk of coronary revascularization (HR, 0.78; 95% CI, 0.67-0.91) and death (HR, 0.70; 95% CI, 0.62-0.79) than those who used BMSs. However, the risks of myocardial infarction (HR, 0.89; 95% CI, 0.66-1.18), ischemic stroke (HR, 1.02; 95% CI, 0.67-1.53) and major bleeding (HR, 0.80; 95% CI, 0.56-1.14) were similar between the two groups.

CONCLUSIONS

Among patients with CS complicating AMI, DES implantation significantly reduced the risk of percutaneous coronary revascularization and death compared to BMS implantation.

Impact of Chronic Kidney Disease on Short-Term Cardiac Implantable Electronic Device Related Infection: A Nationwide Population-Based Cohort Study

Chronic kidney disease (CKD) increased the incident cardiac implantable electronic device (CIED) infection, but risk factors of CIED infection in CKD patients remain unclear.Patients who received new CIED implantation between January 1, 1997 and December 31, 2011 were selected from the Taiwan National Health Insurance Database and were divided into 3 groups: patients with normal renal function, CKD patients without dialysis, and CKD patient with dialysis. Two outcomes, CIED infection during index hospitalization and within 1 year after discharge, were evaluated.This study included 38,354 patients, 35,060 patients in normal renal function group, 1927 patients in CKD without dialysis group, and 1367 patients in CKD with dialysis group. CKD patients without dialysis (adjusted odds ratio [aOR], 2.14, 95% confidence interval [CI], 1.32-3.46) and CKD patients with dialysis (aOR, 3.78, 95% CI, 2.37-6.02) increased incident CIED infection during index hospitalization compared to patients with normal renal function. Use of steroid (aOR: 2.74, 95% CI, 1.08-6.98) increased the risk of CIED infection in CKD patients without dialysis while chronic obstructive pulmonary disease (COPD) (aOR: 2.76, 95% CI, 1.06-7.16) increased the risk of CIED infection in CKD patient with dialysis during index hospitalization.CKD is a risk of CIED infection during index hospitalization. Use of steroid and COPD are important risks factors for CIED infection in CKD patients.

Clinical Outcomes of Drug-Eluting Stents vs. Bare-Metal Stents in Acute Myocardial Infarction Patients Under Dialysis - A Nationwide Cohort Study

BACKGROUND

Data on the cardiovascular (CV) outcomes of drug-eluting stents (DES) vs. bare-metal stents (BMS) in patients with acute myocardial infarction (AMI) under dialysis are limited.

METHODS AND RESULTS

We analyzed the data from 42,592 AMI patients in the Taiwan National Health Insurance Research Database between 1 January 2007 and 31 December 2011. A total of 984 AMI patients under dialysis were selected as the study cohort. We evaluated the clinical outcomes by comparing 492 subjects who had DES to 492 matched subjects who had BMS. The primary composite outcomes, which included recurrent MI, coronary revascularization and CV death, were significantly lower in the DES group than in the BMS group (41.7% vs. 47.6%, hazard ratio (HR), 0.77; 95% confidence interval (CI), 0.63-0.92, P=0.005) after mean 1.2 years. The patients who received DES had a lower risk of recurrent MI (HR, 0.63; 95% CI, 0.45-0.90), CV death (HR, 0.74; 95% CI, 0.56-0.98) and all-cause mortality (HR, 0.74; 95% CI, 0.61-0.89) than those who used BMS, but a similar risk of major bleeding (HR, 0.99; 95% CI, 0.69-1.42, P=0.952) and ischemic stroke (HR, 1.15; 95% CI, 0.66-2.01, P=0.631).

CONCLUSIONS

Among AMI patients on dialysis undergoing percutaneous coronary interventions, DES implantation significantly reduced the risk of recurrent MI, CV death and all-cause mortality compared with BMS implantation.

Impact of Asthma on the Development of Coronary Vasospastic Angina: A Population-Based Cohort Study

Although asthma increases the risk of cardiovascular disease, little is known about the relation of asthma and its severity to coronary vasospastic angina (CVsA). We hypothesized that asthma contributed to the development of CVsA.Patients in this population-based cohort study were retrospectively collected from the Taiwan National Health Insurance database. Using propensity score matching, subjects were stratified at a 1 : 4 ratio into a study group comprising 3087 patients with a diagnosis of CVsA, and a control group consisting of 12,348 patients who underwent coronary intervention for obstructive coronary artery disease (CAD) during the period 2000 to 2011.Asthma significantly increased the risk of new-onset CVsA independent of other comorbidities [adjusted odds ratio (OR) = 1.85, 95% confidence interval (95% CI) = 1.47-2.32, P < 0.001]. In addition, the risk of new-onset CVsA was significantly higher in previous users of oral or inhaled corticosteroids (oral corticosteroids: OR = 1.22, 95% CI = 1.01-1.49, P = 0.04; inhaled corticosteroids: OR = 1.89, 95% CI = 1.28-2.79, P = 0.001). In addition, the prevalence of asthma was highest among patients with CVsA alone, followed by patients with CAD and CVsA and patients who underwent coronary intervention for CAD alone (P trend < 0.001).Our study suggests that asthma is independently associated with CVsA and prior steroid use increases the risk of CVsA development.

In-Hospital and 4-Year Clinical Outcomes Following Transcatheter Versus Surgical Closure for Secundum Atrial Septal Defect in Adults: A National Cohort Propensity Score Analysis

Atrial septal defect (ASD) closure is major therapy for patients with secundum ASD. Although surgical closure (SC) and transcatheter closure (TC) are usually performed in such patients, data on the long-term outcomes comparing TC and SC in adults are limited. Data on the participants of this cohort study were retrieved from Taiwan's National Health Insurance Research Database from 2004 to 2011. Secundum ASD patients > 18 years of age who underwent TC or SC were initially enrolled, and those with associated comorbidities were excluded. After propensity score matching, the clinical outcomes between the TC and SC groups were analyzed. There were 595 patients recruited in the TC group and 308 patients in the SC group. The SC group had a higher incidence of systemic thromboembolism (P < 0.001), ischemic stroke (P = 0.002), and all-cause mortality (P = 0.013) when compared with those of the TC group at the index hospitalization, and similar phenomena could also be seen in a around 4-year follow-up period after the procedures (systemic thromboembolism (P < 0.001, HR = 11.48, 95% CI: 3.29-40.05), ischemic stroke (P = 0.005, HR = 9.28, 95% CI: 1.94-44.39), and all-cause mortality (P = 0.035, HR = 2.28, 95% CI: 1.06-4.89). In addition, atrial fibrillation (P = 0.005) and atrial flutter (P = 0.049) more frequently developed in the SC group than in the TC group at the index hospitalization. The adult secundum ASD patients had lower incidence rates of systemic thromboembolism, ischemic stroke, and all-cause mortality after TC than those after SC in the 4-year follow-up after procedures. Transcatheter ASD closure should therefore be given priority.

Sitagliptin After Ischemic Stroke in Type 2 Diabetic Patients: A Nationwide Cohort Study

The cerebrovascular safety and efficacy of sitagliptin, a dipeptidyl peptidase-4 inhibitor, in patients with type 2 diabetes mellitus (T2DM) with ischemic stroke remains uncertain. The aim of this study was to assess the efficacy and safety of sitagliptin in patients with T2DM with recent ischemic stroke. We analyzed data from the Taiwan National Health Insurance Research Database between March 1, 2009, and December 31, 2011. Ischemic stroke patients were identified from individuals with T2DM. Patients who received sitagliptin were compared with those who did not to evaluate the cardiovascular safety and efficacy of sitagliptin. The primary outcome was a composite of ischemic stroke, myocardial infarction, or cardiovascular death. A total of 5145 type 2 diabetic patients with ischemic stroke met our inclusion criteria and were followed for up to 2.83 years (mean, 1.17 years). Overall, 1715 patients (33.3%) received sitagliptin and 3430 patients (66.7%) did not. The primary composite outcome occurred in 190 patients in the sitagliptin group (11.1%) and in 370 patients in the comparison group (10.8%) (hazard ratio [HR] = 1.02; 95% confidence interval [CI], 0.85-1.21). Patients treated with sitagliptin had a similar risk of ischemic stroke, hemorrhagic stroke, and all-cause mortality with an HR of 0.95 (95% CI, 0.78-1.16, P = 0.612), 1.07 (95% CI, 0.55-2.11, P = 0.834), and 1.00 (95% CI, 0.82-1.22, P = 0.989), respectively, compared with patients not treated with sitagliptin. Treatment with sitagliptin in type 2 diabetic patients with recent ischemic stroke was not associated with increased or decreased risks of adverse cerebrovascular outcomes.

Cardiovascular Outcomes of Sitagliptin in Type 2 Diabetic Patients with Acute Myocardial Infarction, a Population-Based Cohort Study in Taiwan

Background

The cardiovascular safety and efficacy of sitagliptin, a dipeptidyl peptidase 4 (DPP-4) inhibitor, in type 2 diabetic patients after acute myocardial infarction (AMI) has so far remained uncertain.

Methods

We analyzed data from the National Health Insurance Research Database (NHIRD), a government-operated, population-based database, from March 1st, 2009 to December 31st, 2011. Type 2 diabetic patients hospitalized for AMI were included in our study. We compared subjects using sitagliptin with comparison group to evaluate its cardiovascular safety and efficacy. The primary endpoint was a composite of cardiovascular death, myocardial infarction, and ischemic stroke.

Results

We identified a total of 3,282 type 2 diabetic patients hospitalized for AMI (mean follow-up 1.15 years). Of these patients, 547 (16.7%) who were exposed to sitagliptin were defined as the sitagliptin group and 2,735 (83.3 %) who did not use sitagliptin were the comparison group. The incidence of primary composite cardiovascular outcomes was 9.50 per 100 person-years in the sitagliptin group and was 9.70 per 100 person-years in the comparison group (hazard ratio (HR), 0.97; 95% CI, 0.73–1.29, P=0.849). Compared to the non-sitagliptin group, the sitagliptin group had similar risks of all-cause mortality, hospitalization for heart failure (HF) or percutaneous coronary intervention (PCI) with a HR of 0.82 (95% CI, 0.61–1.11, P=0.195), 0.93 (95% CI, 0.67–1.29, P=0.660), and 0.93 (95% CI, 0.75–1.14, P=0.473), respectively.

Conclusion

The use of sitagliptin in type 2 diabetic patients with recent AMI was not associated with increased risk of adverse cardiovascular events.

Pericardiocentesis adverse event risk factors: a nationwide population-based cohort study

OBJECTIVES

Echocardiography-guided pericardiocentesis has been the leading procedure for diagnosis and therapy of pericardial effusion. We aimed to identify risk factors for recurrence, complications, and mortality in pericardial effusion patients treated with pericardiocentesis.

METHODS

We identified and collected data from 8,101 patients receiving pericardiocentesis between 1997 and 2010 from the Taiwan National Health Insurance Research Database. A multivariate regression model was used to investigate risk factors for recurrence, complications, and death.

RESULTS

There were 8,565 admissions among 8,101 patients. The most common underlying condition was malignancy (41%), especially lung cancer (23%), tuberculosis (9.0%), and acute pericarditis (8.2%). Surgical drainage was required in 12.7% of cases. Recurrence was more likely in patients with malignancy (HR 2.20, p < 0.001), but complications were less likely (OR 0.52, p = 0.003). In-hospital death numbers and complication risks (OR 2.38, p < 0.001; OR 1.27, p = 0.01) were greater in the catheter-related cardiac procedure group than in the other groups.

CONCLUSIONS

Malignant neoplasms and catheter-based cardiac procedures have become major risk factors for adverse events in patients receiving pericardiocentesis in Taiwan. Malignancy leads to an increase in recurrence and in-hospital mortality but is associated with a lower rate of acute complications. Cardiac catheterization procedures and surgery increase both complications and in-hospital mortality.

Sitagliptin and cardiovascular outcomes in diabetic patients with chronic kidney disease and acute myocardial infarction: A nationwide cohort study

BACKGROUND

The cardiovascular safety and efficacy of sitagliptin, a dipeptidyl peptidase 4 (DPP-4) inhibitor, in type 2 diabetic patients with chronic kidney disease (CKD) after acute myocardial infarction (AMI) are unclear.

METHODS

We analyzed data from the Taiwan National Health Insurance Research Database between March 1st, 2009 and December 31st, 2011. A total of 1025 AMI patients with diabetes with chronic kidney disease were selected as the study cohort. The study evaluated the cardiovascular safety and efficacy of sitagliptin by comparing 205 subjects (20%) who use sitagliptin to 820 matched subjects (80%) who do not. The primary outcomes included myocardial infarction, ischemic stroke or cardiovascular death.

RESULTS

Primary composite outcomes occurred in 54 patients in the sitagliptin group (26.3%) and in 164 patients in the comparison group (20.0%) (HR, 1.32; 95% CI, 0.97-1.79; P=0.079) during the mean follow-up of 1.02years (SD=0.71years). The sitagliptin group had similar risks of ischemic stroke, all-cause mortality or hospitalization for heart failure (HF) compared to the non-sitagliptin group (P=0.938, 0.523 and 0.795 respectively). However, sitagliptin use was associated with increased risks of recurrent myocardial infarction (HR, 1.73; 95% CI, 1.15-2.58; P=0.008) and percutaneous coronary revascularization (HR, 1.43; 95% CI, 1.04-1.95; P=0.026).

CONCLUSIONS

Among type 2 diabetic patients with CKD after AMI, the use of sitagliptin was not associated with an increased risk of cardiovascular death, ischemic stroke or hospitalization for HF but was associated with increased risks of recurrent MI and percutaneous coronary revascularization.

Outcomes and characteristics of patients undergoing percutaneous angioplasty followed by below-knee or above-knee amputation for peripheral artery disease

OBJECTIVE

Little is known about long-term outcomes among patients who receive percutaneous angioplasty (PTA) for peripheral artery disease (PAD) then undergo below-knee or above-knee amputations. We sought to determine clinical outcomes associated with below-knee or above-knee amputation, along with possible explanatory factors and treatment strategies.

METHODS

Using data from Taiwan's National Health Insurance Research Database from 1997 to 2010, 7,568 adult patients were divided into three groups: lower extremity preserved (LE), below-knee amputation (BK) and above-knee amputation (AK). We assessed outcomes including major adverse cardiovascular events (MACE) and associated risk factors.

RESULTS

Overall MACE was significantly higher in the AK group compared to the LE and BK groups, over a mean follow-up of 2.45 years (hazard ratio [HR]: 1.81; 95% confidence interval [CI]: 1.50-2.18 for AK vs. LE; HR: 1.67; 95% CI: 1.36-2.06 for AK vs. BK). However MACE were similar for the BK and LE groups (HR: 1.08; 95% CI: 0.98-1.20). Overall mortality was highest in the AK group (HR: 1.65, 95% CI: 1.34-2.04 for AK vs. BK). As for patient characteristics, atrial fibrillation was more prevalent in the AK group than in the BK group (17% vs. 7%). Independent risk factors associated with death after above- or below-knee amputation included advanced age, heart failure, dialysis, male gender and high patient volume.

CONCLUSION

The MACE rate was highest in the AK group, whereas the LE and BK groups were similar in this regard. Furthermore, overall mortality increased with larger area of amputation.

Differences of left ventricular systolic deformation in hypertensive patients with and without apical hypertrophic cardiomyopathy

BACKGROUND

We tested the hypothesis that the apical myocardial mechanics differ from those of other ventricular segments in hypertensive patients with and without apical hypertrophic cardiomyopathy (ApHCM).

METHODS

We retrospectively studied hypertensive patients with and without ApHCM. Left ventricular longitudinal, circumferential, and radial strains were examined by two-dimensional speckle-tracking echocardiography at the basal, middle, and apical walls of the parasternal short-axis and apical 2-, 3- and 4-chamber views.

RESULTS

Fourteen consecutive patients with hypertension and ApHCM and 14 patients with hypertension without ApHCM were studied. Lower mitral annular peak systolic velocity and greater diastolic dysfunction were present in hypertensive patients with ApHCM than in hypertensive patients without ApHCM. Compared with hypertensive patients without ApHCM, hypertensive patients with ApHCM had significantly lower apical longitudinal (-13.9% vs -21.9%, p = 0.010) and radial strains (4.4% vs 11.5%, p = 0.017) without the base-to-apex gradient. The global longitudinal (-15.6% vs -18.8%, p = 0.027) and circumferential strains (-16.1% vs -19.2%, p = 0.019) were significantly lower in hypertensive patients with ApHCM than in hypertensive patients without ApHCM. Among systolic parameters, the global longitudinal strain was independently associated with hypertension with ApHCM (odds ratio, 1.457; 95% confidence interval, 1.002-2.119; p = 0.049).

CONCLUSIONS

Reduced apical longitudinal and radial strains without a base-to-apex gradient were present in hypertensive patients with ApHCM. The global longitudinal strain was independently associated with ApHCM in hypertensive patients.

In vitro and in vivo activities of oligodeoxynucleotide-based thrombin inhibitors containing neutral formacetal linkages

A series of 15-mer oligodeoxynucleotide analogues were synthesized, and their thrombin inhibitory activities in vitro and in vivo were evaluated. These oligodeoxynucleotide analogues share the same sequence (GGTTGGTGTGGTTGG) but have one or more phosphodiester linkages replaced by a neutral formacetal group. The results obtained from monosubstitutions show that no single phosphodiester group is critical for the thrombin inhibitory activity, suggesting that the interaction between the oligodeoxynucleotide and thrombin is based on a multiple-site charge-charge interaction. Analysis of the effects of different phosphodiester replacements indicates that the backside and left side of the chairlike structure formed by the molecule may be involved in binding with thrombin, presumably by having direct contacts with the anion-binding exosite of the enzyme. For the oligodeoxynucleotides containing two noncontiguous formacetal groups, the effect of the disubstitution is the sum of the effects obtained from the corresponding two monosubstitutions. Infusion of an oligodeoxynucleotide containing four formacetal groups into monkeys showed an increased in vivo anticoagulant effect and an extended in vivo half-life compared to the unmodified oligodeoxynucleotide.

Protein engineering thrombin for optimal specificity and potency of anticoagulant activity in vivo

Previous alanine scanning mutagenesis of thrombin revealed that substitution of residues W50, K52, E229, and R233 (W60d, K60f, E217, and R221 in chymotrypsinogen numbering) with alanine altered the substrate specificity of thrombin to favor the anticoagulant substrate protein C. Saturation mutagenesis, in which residues W50, K52, E229, and R233 were each substituted with all 19 naturally occurring amino acids, resulted in the identification of a single mutation, E229K, that shifted the substrate specificity of thrombin by 130-fold to favor the activation of the anticoagulant substrate protein C over the procoagulant substrate fibrinogen. E229K thrombin was also less effective in activating platelets (18-fold), was resistant to inhibition by antithrombin III (33-fold and 22-fold in the presence and absence of heparin), and displayed a prolonged half-life in plasma in vitro (26-fold). Thus E229K thrombin displayed an optimal phenotype to function as a potent and specific activator of endogenous protein C and as an anticoagulant in vivo. Upon infusion in Cynomolgus monkeys E229K thrombin caused an anticoagulant effect through the activation of endogenous protein C without coincidentally stimulating fibrinogen clotting and platelet activation as observed with wild-type thrombin. In addition, E229K thrombin displayed enhanced potency in vivo relative to the prototype protein C activator E229A thrombin. This enhanced potency may be attributable to decreased clearance by antithrombin III, the principal physiological inhibitor of thrombin.

Conversion of thrombin into an anticoagulant by protein engineering

At sites of vascular injury, thrombin interacts with multiple procoagulant substrates, to mediate both fibrin clotting and platelet aggregation. But upon binding to thrombomodulin on the vascular endothelium, thrombin instead activates protein C, thereby functioning as an anticoagulant and attenuating clot formation. Upon infusion in vivo, both the procoagulant and anticoagulant effects of thrombin were observed. Preliminary studies indicating that thrombin's protein C activating and fibrinogen clotting activities could be dissociated by mutagenesis suggested to us that a thrombin variant that lacked procoagulant activity while retaining anticoagulant function might be an attractive antithrombotic agent. Using protein engineering, we introduced a single substitution, E229A, that substantially shifted thrombin's specificity in favour of the anticoagulant substrate, protein C. In monkeys, this modified thrombin functioned as an endogenous protein C activator demonstrating dose-dependent, reversible anticoagulation without any indication of procoagulant activity. Notably, template bleeding times were not prolonged, suggesting a reduced potential for bleeding complications.

A peptide derived from a tissue factor loop region functions as a tissue factor--factor VIIa antagonist

Tissue factor (TF) is a transmembrane protein that functions in the initiation of blood coagulation in vivo. At sites of vascular injury, TF serves as a cell-surface receptor for the serine protease factor VIIa (FVIIa), forming an enzyme--cofactor complex and enhancing the catalytic activity of FVIIa. Tissue factor, along with the receptors for alpha- and gamma-interferons, is a member of the class 2 cytokine receptor superfamily. Crystallographic analysis demonstrated that the extracellular domain of TF consists of two immunoglobulin-like domains joined by a linker region. Each domain is comprised of two antiparallel beta-sheets containing seven conserved beta-strands separated by more variable loop regions. Extensive mutagenesis has been performed in order to map the FVIIa binding site on TF. Results indicated that the discontinuous binding site for FVIIa lies at the domain--domain interface and includes residues from extended loops and beta-strands within both the N- and C-terminal domains. Our previous study provided evidence that three consecutive residues (D44, W45, K46) within the TF loop region between beta-strands C and C' of the N-terminal domain were important for interactions with FVIIa. We have presently extended our alanine-scanning mutagenesis to include the residues within the flanking beta-strands. Thirteen sTF mutants were screened for their ability to enhance FVIIa activity. Three residues within strand C (Y34, Q37, I38) and two residues within C' (K48, Y51) were shown to be important for TF cofactor function.(ABSTRACT TRUNCATED AT 250 WORDS)