Impact of coronary CT angiography in selection of treatment modalities and subsequent cardiovascular events in Thai patients with stable CAD

BACKGROUND

Coronary computed tomography angiography (CCTA) enables improved diagnosis of subclinical, coronary artery disease (CAD). This retrospective cohort study investigated the association between different treatment modalities guided by CCTA and the prevention of major adverse cardiovascular events (MACEs) in patients with stable CAD.

METHODS

From 2005 to 2013, a total of 9338 patients, including both asymptomatic individuals with risk factors and symptomatic patients with suspected CAD, who underwent CCTA were analyzed. The patients were categorized into one of three groups based on results of CCTA: obstructive CAD (≥ 50% stenosis in at least one vessel), non-obstructive CAD (1-49% stenosis in at least one vessel), and no observed CAD (0% stenosis). They were subsequently followed up to assess the treatment they received and the occurrence of MACEs (cardiovascular death, non-fatal myocardial infarction, non-fatal stroke, or late revascularization).

RESULTS

During an average follow-up period of 9.9 ± 2.4 years, patients with obstructive CAD had the highest incidence of MACEs (19.8%), followed by those with non-obstructive CAD and no coronary artery stenosis (10.3 and 5.5%, respectively). After adjusting for confounding variables, it was found that patients treated with statins alone were the least likely to develop MACEs in all three groups, compared to those receiving no treatment, with hazard ratios (95% CI) of 0.43 (0.32, 0.58), 0.47 (0.34, 0.64), and 0.46 (0.31, 0.69), respectively. In patients with obstructive CAD, treatment with a combination of statin and aspirin, or early revascularization was associated with a lower likelihood of experiencing MACEs compared to no treatment with hazard ratios of 0.43 (0.33, 0.58) and 0.64 (0.43, 0.97), respectively.

CONCLUSION

CCTA offers useful guidance for the treatment of patients with stable CAD and shows potential for prevention of CV events. However, the full validation of a given strategy utilizing CCTA will require a prospective longitudinal study, utilizing a randomized clinical trial design.

Updated CRUSADE score to predict in-hospital bleeding: External validation in the Thai percutaneous coronary intervention registry

BACKGROUND

The Can Rapid Risk Stratification of Unstable Angina Patients Suppress Adverse Outcomes with Early Implementation of the ACC/AHA Guidelines (CRUSADE) score has been recommended to predict in-hospital bleeding risk in non-ST segment elevation myocardial infarction (NSTEMI) patients. The evaluation of the CRUSADE risk score in Asian patients undergoing contemporary percutaneous coronary intervention (PCI) for NSTEMI is necessary.

AIMS

We aimed to validate and update the CRUSADE score to predict in-hospital major bleeding in NSTEMI patients treated with PCI.

METHOD

The Thai PCI registry is a large, prospective, multicenter PCI registry in Thailand enrolling patients between May 2018 and August 2019. The CRUSADE score was calculated based on 8 predictors including sex, diabetes, prior vascular disease (PVD), congestive heart failure (CHF), creatinine clearance (CrCl), hematocrit, systolic blood pressure, and heart rate (HR). The score was fitted to in-hospital major bleeding using the logistic regression. The original score was revised and updated for simplification.

RESULTS

Of 19,701 patients in the Thai PCI registry, 5976 patients presented with NSTEMI. The CRUSADE score was calculated in 5882 patients who had all variables of the score available. Thirty-five percent were female, with a median age of 65.1 years. The proportion of diabetes, PVD, and CHF was 46%, 7.9%, and 11.2%, respectively. The original and revised models of the CRUSADE risk score had C-statistics of 0.817 (95% CI: 0.762-0.871) and 0.839 (95% CI: 0.789-0.889) respectively. The simplified CRUSADE score which contained only four variables (hematocrit, CrCl, HR, and CHF), had C-statistics of 0.837 (0.787-0.886). The calibration of the recalibrated, revised, and simplified model was optimal.

CONCLUSIONS

The full and simplified CRUSADE scores performed well in NSTEMI treated with PCI in Thai population.

Factors associated with health-related quality of life in patients undergoing percutaneous coronary intervention: Thai PCI registry

Background

Percutaneous coronary intervention (PCI) has been shown to improve health-related quality of life (HRQoL) in patients with coronary artery disease (CAD). The objectives of this study were to assess the changes in HRQoL and factors influencing these changes in CAD patients after undergoing PCI.

Methods

Data from a nationwide PCI registry across 39 hospitals in Thailand were collected in 2018-2019, including baseline characteristics, comorbid diseases, angiographic CAD severity, procedural details, and type of health insurance. HRQoL, as measured by utility scores, was determined in all patients using the Thai version of EQ-5D-5l at admission, discharge, and 6 and 12 months after discharge. The effects of time after PCI procedure and various factors on mean utility scores were assessed using a mixed-effect linear regression model.

Results

A total of 19,701 patients were included in the analysis; they had a mean age of 64.2 ± 11.7 years and were predominantly (69.1%) male. Following PCI, the mean utility scores increased from 66.6 ± 19.6 at admission to 81.9 ± 13.8 at discharge, and remained stable at 6 and 12 months (86.1 ± 12.3 and 88.0 ± 11.7, respectively). After adjusting for potential confounding variables, several factors were found to be independently associated with improved HRQoL, including angiographic success, male gender, overweight status, dyslipidemia, and radial access. Six other factors were associated with less improved HRQoLs, including cardiogenic shock/IABP support, old age, CKD, clinical presentation (STEMI and NSTEMI), prior cerebrovascular disease, and heart failure. There were no associations of CAD severity and procedural details with HRQoL. No differences were found related to type of health insurance, except that patients who were uninsured or self-pay tended to have less improvement in HRQoL.

Conclusion

HRQoL improved significantly after PCI in these subjects, as observed through 1 year of follow-up. Identifying the factors influencing these improvements may assist clinicians in tailoring patient interventions to optimise quality of life after PCI.

Utility of coronary artery calcium in refining 10-year ASCVD risk prediction using a Thai CV risk score

Background

Coronary artery calcium (CAC) scanning is a valuable additional tool for calculating the risk of cardiovascular (CV) events. We aimed to determine if a CAC score could improve performance of a Thai CV risk score in prediction of 10-year atherosclerotic cardiovascular disease (ASCVD) risk for asymptomatic patients with CV risk factors.

Methods

This was a retrospective cohort study that enrolled asymptomatic patients with CV risk factors who underwent CAC scans between 2005 and 2013. The patients were classified as low-, intermediate-, or high-risk (<10%, 10%-<20%, and ≥20%, respectively) of having ASCVD within 10-years based on a Thai CV risk score. In each patient, CAC score was considered as a categorical variable (0, 1-99, and ≥100) and natural-log variable to assess the risk of developing CV events (CV death, non-fatal MI, or non-fatal stroke). The C statistic and the net reclassification improvement (NRI) index were applied to assess whether CAC improved ASCVD risk prediction.

Results

A total of 6,964 patients were analyzed (mean age: 59.0 ± 8.4 years; 63.3% women). The majority of patients were classified as low- or intermediate-risk (75.3% and 20.5%, respectively), whereas only 4.2% were classified as high-risk. Nearly half (49.7%) of patients had a CAC score of zero (no calcifications detected), while 32.0% had scores of 1-99, and 18.3% of ≥100. In the low- and intermediate-risk groups, patients with a CAC ≥100 experienced higher rates of CV events, with hazard ratios (95% CI) of 1.95 (1.35, 2.81) and 3.04 (2.26, 4.10), respectively. Incorporation of ln(CAC + 1) into their Thai CV risk scores improved the C statistic from 0.703 (0.68, 0.72) to 0.716 (0.69, 0.74), and resulted in an NRI index of 0.06 (0.02, 0.10). To enhance the performance of the Thai CV risk score, a revision of the CV risk model was performed, incorporating ln(CAC + 1), which further increased the C statistic to 0.771 (0.755, 0.788).

Conclusion

The addition of CAC to traditional risk factors improved CV risk stratification and ASCVD prediction. Whether this adjustment leads to a reduction in CV events and is cost-effective will require further assessment.

Validation of the academic research consortium high bleeding risk definition in Thai PCI registry

BACKGROUND

Bleeding following percutaneous coronary intervention (PCI) has important prognostic implications. The Academic Research Consortium (ARC) have identified a set of clinical criteria to standardize the definition of a high bleeding risk (HBR). Current study sought to externally validate the ARC definition for HBR patients in a contemporary real-world cohort.

METHOD

This post hoc analysis included 22,741 patients undergoing PCI between May 2018 and August 2019 enrolled in Thai PCI Registry. The primary endpoint was the incidence of major bleeding at 12 months post index PCI.

RESULTS

In total, 8678 (38.2%) and 14,063 (61.8%) patients were stratified to the ARC-HBR and non-ARC-HBR groups, respectively. Incidence of major bleeding was 3.3 and 1.1 per 1000 patients per month in the ARC-HBR group and the non-ARC-HBR group (HR 2.84 [95% CI: 2.39-3.38]; p < 0.001). Advanced age and heart failure met the 1-year major criteria performance goal of ≥4% major bleeding. The impact of HBR risk factors was incremental. HBR patients also experienced significantly higher rates of all-cause mortality (19.1% versus 5.2%, HR 4.00 [95% CI: 3.67-4.37]; p < 0.001) and myocardial infarction. The ARC-HBR score fairly performed in discriminating bleeding with C-statistic (95% CI) of 0.674 (0.649, 0.698). Updating the ARC-HBR by adding heart failure, prior myocardial infarction, non-radial access, female in the model significantly improved C-statistic of 0.714 (0.691, 0.737).

CONCLUSIONS

The ARC-HBR definition could identify patients at increased risk not only for bleeding but also for thrombotic events, including all-cause mortality. Coexistence of multiple ARC-HBR criteria unveiled additive prognostic value.

Evaluation of transitions from early hypertension to hypertensive chronic kidney disease, coronary artery disease, stroke and mortality: a Thai real-world data cohort

Objective

Systemic arterial hypertension (HT) is a major modifiable risk factor for cardiovascular disease (CVDs), associated with all-cause death (ACD). Understanding its progression from the early state to late complications should lead to more timely intensification of treatment. This study aimed to construct a real-world cohort profile of HT and to estimate transition probabilities from the uncomplicated state to any of these long-term complications; chronic kidney disease (CKD), coronary artery disease (CAD), stroke, and ACD.

Methods

This real-world cohort study used routine clinical practice data for all adult patients diagnosed with HT in the Ramathibodi Hospital, Thailand from 2010 to 2022. A multi-state model was developed based on the following: state 1-uncomplicated HT, 2-CKD, 3-CAD, 4-stroke, and 5-ACD. Transition probabilities were estimated using Kaplan-Meier method.

Results

A total of 144,149 patients were initially classified as having uncomplicated HT. The transition probabilities (95% CI) from the initial state to CKD, CAD, stroke, and ACD at 10-years were 19.6% (19.3%, 20.0%), 18.2% (17.9%, 18.6%), 7.4% (7.1%, 7.6%), and 1.7% (1.5%, 1.8%), respectively. Once in the intermediate-states of CKD, CAD, and stroke, 10-year transition probabilities to death were 7.5% (6.8%, 8.4%), 9.0% (8.2%, 9.9%), and 10.8% (9.3%, 12.5%).

Conclusions

In this 13-year cohort, CKD was observed as the most common complication, followed by CAD and stroke. Among these, stroke carried the highest risk of ACD, followed by CAD and CKD. These findings provide improved understanding of disease progression to guide appropriate prevention measures. Further investigations of prognostic factors and treatment effectiveness are warranted.

External Validation of the ACUITY/HORIZON Bleeding Risk Score among Acute Coronary Syndrome Patients in Thai PCI Registry

BACKGROUND

 External validation is essential before implementing a predictive model in clinical practice. This analysis validated the performance of the ACUITY/HORIZON risk score in the most contemporary Thai PCI registry.

METHODS

 The ACUITY/HORIZON model was applied and validated externally in 12,268 ACS (acute coronary syndrome) patients. For revision and updating models, the regression coefficientd of all predictors were re-estimated and then additional predictors were stepwise selected from multivariate analysis.

RESULTS

 In-hospital bleeding defined by the BARC (Bleeding Academic Research Consortium) criteria was 1.3% (161 patients) and 2.3% (285 patients) by the ACUITY criteria. The calibration of both scales demonstrated overestimation of the original model with C-statistic values of 0.704 for ACUITY major bleeding and 0.793 for BARC 3 or 5 bleeding. For ACUITY major bleeding, the discriminatory power of the update model improved substantially when congestive heart failure (CHF), prior vascular disease as well as body mass index were considered. The update model demonstrated good calibration and C-statistic of 0.747 and 0.745 with no white blood cell (WBC) count. For BARC 3 or 5 bleeding, good calibration and discriminatory capacity could be observed when CHF and prior vascular disease were added in the update models, with an excellent C-statistic of 0.838, and a lower C-statistic value of 0.835 was obtained in the absence of WBC count.

CONCLUSION

 The ACUITY/HORIZON score was successfully validated in contemporary predictive and risk-adjustment models for PCI-related bleeding. The update models had good operating characteristics in patients from a real-world ACS population irrespective of bleeding definitions.

Predictive values of coronary artery calcium and arterial stiffness for long-term cardiovascular events in patients with stable coronary artery disease

BACKGROUND

Subclinical atherosclerosis detected by increased coronary artery calcium (CAC) or arterial stiffness as reflected by cardio-ankle vascular index (CAVI) has been associated with major adverse cardiovascular events (MACEs). However, comparative data from these two assessments in the same population are still limited.

METHODS

From 2005 to 2013, patients with stable coronary artery disease (CAD), both asymptomatic and symptomatic who underwent both coronary computed tomography and CAVI were enrolled and followed for occurrence of MACEs (cardiovascular [CV] death, nonfatal myocardial infarction [MI], and nonfatal stroke) until December 2019. A cause-specific hazard model was applied to assess the associations of CAC score, and CAVI with long-term MACEs.

RESULTS

A total of 8687 patients participated. Of them, CAC scores were 0, 1-99, 100-399, and ≥400 in 49.7%, 31.9%, 12.3%, and 6.1%, respectively. Arterial stiffness (CAVI ≥ 9.0) was associated with the magnitude of CAC in 23.8%, 36.3%, 44.5%, and 56.2%, respectively. During an average of 9.9 ± 2.4 years follow-up, MACEs occurred in 8.0% (95% CI: 7.4%, 8.6%) of subjects. After adjusting for covariables, CAC scores of 100-399 and ≥400, and CAVIs of ≥9.0 were found to independently predict the occurrence of MACEs with the hazard ratios (95% CI) of 1.70 (1.13, 1.98), 1.87 (1.33, 2.63), and 1.27 (1.06, 1.52), respectively. Other risk predictors were hypertension, diabetes mellitus (DM), chronic kidney disease (CKD), aspirin, and statin therapy.

CONCLUSIONS

A CAC score ≥100 or a CAVI ≥ 9.0 predicts the long-term occurrence of MACEs in both asymptomatic and symptomatic patients with stable CAD. These two noninvasive tests can be used as screening tools to guide treatment for the prevention of future CV events.

Dose-dependent effect of impaired renal function on all-cause mortality in patients following percutaneous coronary intervention

Objective

To determine the risk prediction of various degrees of impaired renal function on all‐cause mortality in patients following percutaneous coronary intervention (PCI).

Background

Patients with chronic kidney disease (CKD) are at high risk of all‐cause mortality after PCI. However, there are less data of various degrees of impaired renal function to predict those risks.

Methods

This was a subgroup analysis of nationwide PCI registry of 22 045 patients. Patients were classified into six CKD stages according to preprocedure estimated glomerular filtration rate (eGFR) (ml/min/1.73 m²): I (≥90), II (60−89), III (30−59), IV (15−29), or V (<15) without or with dialysis. Baseline clinical and angiographic characteristics were compared among patients in each stage. One‐year all‐cause mortality was reported with risk prediction based on CKD stages and other risk factors.

Results

Patients with CKD stage I−V without and with on dialysis were found in 26.9%, 40.8%, 23.2%, 3.9%, 1.5%, and 3.7%, respectively. PCI procedural success and complication rates ranged from 94.0% to 96.2% and 2.8% to 6.1%, respectively. One‐year overall survival among CKD stages I−V was 96.3%, 93.1%, 84.4%, 65.2%, 68.0%, and 69.4%, respectively (p < .001 by log‐rank test). After adjusting covariables, the hazard ratios of all‐cause mortality for CKD stages II−V as compared to stage I by multivariate Cox regression analysis were 1.5, 2.6, 5.3, 5.9, and 7.0, respectively, (p < .001).

Conclusion

Among patients undergoing PCI, lower preprocedure eGFR is associated in a dose‐dependent effect with decreased 1‐year survival. This finding may be useful for risk classification and to guide decision‐making.

No Paradoxical Effect of Smoking Status on Recurrent Cardiovascular Events in Patients Following Percutaneous Coronary Intervention: Thai PCI Registry

Background

"Smoker's paradox" is a controversial phenomenon that describes an unexpectedly favorable short-term outcome of smokers post-percutaneous coronary intervention (PCI). This study aimed to evaluate the effect of smoking status on recurrent major adverse cardiovascular events (MACEs) in patients who recently underwent PCI and to determine whether it was paradoxical.

Methods

This study utilized data from the nationwide Thai PCI registry, enrolling patients during 2018-2019. Our study factor was smoking status, classified as current smokers, ex-smokers, and nonsmokers. The outcome of interest was the time to occurrence of a composite of MACEs (i.e., all-cause death, myocardial infarction (MI), stroke, and unplanned revascularization) evaluated at about 1-year post-PCI. A propensity score (PS) model using inverse probability weighting with regression adjustment was used to estimate the effect of smoking on the occurrence of MACE.

Results

Current smokers, ex-smokers, and non-smokers accounted for 23, 32, and 45% of the 22,741 subjects, respectively. Smokers were younger, more frequently male, and had fewer traditional atherosclerotic risk factors. Current smokers presented more frequently with ST-elevation MIs (STEMIs) and cardiogenic shock (54 and 14.6%, respectively) than non-smokers. MACE rates were 1.9, 1.2, and 1.6 per 100 patients per month in the current smokers, ex-smokers, and non-smokers, respectively. After applying a PS, patients with a history of current smoking and ex-smoking developed the onset of recurrent MACEs significantly sooner than non-smokers, with a median time of 4.4 vs. 4.9 vs. 13.5 months (p < 0.001), respectively.

Conclusions

"Smoker's paradox" was not observed in our patient population. Current smokers and ex-smokers were prone to develop an earlier onset of a post-PCI MACEs than nonsmokers and need a smoke cessation program for further prevention.

Causal Relationship of Coronary Artery Calcium on Myocardial Infarction and Preventive Effect of Antiplatelet Therapy

Background

The role of coronary artery calcium score (CACS) to guide antiplatelet therapy in order to prevent myocardial infarction (MI) is still uncertain. This study aimed to find the causal relationship of CACS on MI and preventive effect of antiplatelet therapy.

Methods

From 2005 to 2013, all patients with cardiovascular risk factors or symptoms of suspected CAD underwent coronary computed tomography. CACSs were measured using Agatston method and stratified into 4 groups: 0, 1–99, 100–399, and ≥ 400. Antiplatelet therapy was prescribed following physician discretion. Outcomes of interest were MI and bleeding. A mediation analysis was applied to find association pathways. CACS was considered as an independent variable, whereas antiplatelet therapy was considered as a mediator and MI considered the outcome of interest.

Results

A total of 7,849 subjects were enrolled. During an average of 9.9 ± 2.4 years follow-up, MI and bleeding events occurred in 2.24% (n = 176) and 2.82% (n = 221) of subjects, respectively. CACSs 100–399 and CAC ≥ 400 were significantly associated with the development of MI [OR 3.14 (1.72, 5.72), and OR 3.22 (1.66, 6.25), respectively, p < 0.001]. Antiplatelet therapy reduced the risk of MI of these corresponding CAC groups with ORs of 0.60 (0.41, 0.78) and 0.56 (0.34, 0.77), p < 0.001]. A risk of bleeding was associated with antiplatelet therapy (only aspirin), anticoagulant, hypertension, male gender and old age.

Conclusion

CACS was associated with the development of future MI. The preventive effect of antiplatelet therapy was clearly demonstrated in subjects with CACSs equal to or above 100, but this benefit was partially offset by an increased risk of bleeding.

Causal relationship of excess body weight on cardiovascular events through risk factors

Excess body weight is associated with cardiovascular events (CVEs) and premature death. This study aimed to find the causal pathways between excess body weight and CVEs through risk factors in a general adult population. A total of 7921 employees of the Electricity Generating Authority of Thailand were enrolled during 1997-2009. Baseline characteristics and blood test results were collected. A body mass index (BMI) ≥ 23 kg/m², using WHO criteria for Asians was defined as excess body weight. A mediation analysis was applied to assess potential causal pathways. BMI ≥ 23 kg/m² was considered as an independent variable, whereas diabetes mellitus (DM), hypertension (HT), and chronic kidney disease (CKD) were considered as mediators, and CVEs (i.e., fatal and non-fatal coronary artery disease or stroke) were considered as the outcomes. The prevalence of BMI ≥ 23 kg/m², DM, HT, and CKD were 62.7%, 7.8%, 28.1% and 11.8% respectively. During an average of 17.2 ± 5.5 years follow-up, subjects with BMI ≥ 23 kg/m² compared with those with lower BMIs more frequently developed CVEs (9.4 vs 6.2%, P < 0.001). The effects of BMI ≥ 23 kg/m² on CVEs were mediated indirectly through DM and HT with significant ORs of 1.61 (1.34, 2.09) and 1.57 (1.39, 1.80), respectively. The indirect effect of CKD on CVEs was significantly increased if mediated through DM → HT or HT [ORs of 1.17 (1.09, 1.32) and 1.20 (1.10, 1.32), respectively]. Subjects with excess body weight were prone to develop CVEs which were mediated indirectly through DM and HT. The effect of CKD on CVEs was small but enhanced if it occurred as a complication of DM or HT.

Establishment of national diagnostic reference levels for percutaneous coronary interventions (PCIs) in Thailand

PURPOSE

To establish national diagnostic reference levels (DRLs) for percutaneous coronary intervention (PCI) in Thailand for lesions of different complexity.

METHODS

Radiation dose quantity as kerma-area-product (KAP) and cumulative air-kerma at reference point (CAK) from 76 catheterization labs in 38 hospitals in PCI registry of Thailand was transferred online to central data management. Sixteen months data (May 2018 to August 2019) was analyzed. We also investigated role of different factors that influence radiation dose the most.

RESULTS

Analysis of 22,737 PCIs resulted in national DRLs for PCI of 91.3 Gy.cm² (KAP) and 1360 mGy (CAK). The NDRLs for KAP for type C, B2, B1 and A lesions were 106.8, 82.6, 67.9, and 45.3 Gy.cm² respectively and for CAK, 1705, 1247, 962, and 790 mGy respectively. Thus, as compared to lesion A, lesion C had more than double the dose and B2 had nearly 1.6 times and B1 had 1.2 times CAK. Our DRL values are lower than other Asian countries like Japan and Korea and are in the middle range of Western countries. University hospital had significantly higher dose than private or public hospital possibly because of higher load of complex procedures in university hospitals and trainees performing the procedures. Transradial approach showed lower doses than transfemoral approach.

CONCLUSIONS

This large multi-centric study established DRLs for PCIs which can act as reference for future studies. A hallmark of our study is establishment of reference levels for coronary lesions classified as per ACC/AHA and thus for different complexities.

Cardio-ankle vascular index as a predictor of major adverse cardiovascular events in metabolic syndrome patients

Background

Arterial stiffness, as reflected in the cardio‐ankle vascular index (CAVI), is a risk factor for major adverse cardiovascular events (MACEs).

Hypothesis

Combining CAVI and metabolic syndrome (MetS) may enhance prediction of MACEs in a general adult population.

Methods

A total of 3807 employees of the Electricity Generating Authority of Thailand were enrolled in a longitudinal health study during 2007‐2008. Baseline characteristics were collected and CAVI determined. Subjects with previous coronary artery disease or stroke were excluded from analysis. MetS was defined using the modified NCEP‐ATP III for Asians. The primary study endpoint was occurrence of a MACE (myocardial infarction, stroke, or cardiovascular death).

Results

MetS was present in 39.2% at study baseline. The prevalence of CAVI > 9 was higher in subjects with MetS compared to those without (33.7% vs. 28.5%, P = 0.001). During the 12.4 ± 0.6 years follow‐up, 227 participants developed MACEs and 350 died. MetS was more common in patients who developed a MACE (8.2% vs. 5.0%, p < 0.001) than was non‐MetS, but it was not a significant risk after adjusting covariables. Participants with CAVI > 9 had greater risk for MACEs 1.34 (95% CI: 1.01, 1.79) relative to those with CAVI < 9. Participants with both MetS and CAVI > 9 had the worst outcomes, with the highest frequency of MACEs, among the four groups.

Conclusion

Arterial stiffness assessed by CAVI may enhance prediction of future MACEs, adding to the null predictive power of MetS. This index can be used to motivate MetS patients to modify their life‐styles for prevention.

The severity and extent of periodontitis is associated with cardio-ankle vascular index, a novel arterial stiffness parameter

OBJECTIVES

To evaluate the association between the severity and extent of periodontitis and arterial stiffness using the cardio-ankle vascular index (CAVI).

MATERIALS AND METHODS

A cross-sectional study of 2888 Electricity Generation Authority of Thailand (EGAT) employees aged 44-78 years was conducted. The severity of periodontitis was evaluated based on mean clinical attachment level (CAL). The percentage of sites with CAL ≥ 5 mm was used to divide the extent of periodontitis into healthy (0%), localized (> 0-< 30%), and generalized (≥ 30%). The CAVI value, a novel blood pressure-independent arterial stiffness parameter, was analyzed as both continuous and categorical data (low: < 9 or high: ≥ 9). Regression analysis was used to estimate the level of association.

RESULTS

The participants demonstrated a mean CAL, % sites with CAL ≥ 5 mm, and a CAVI value of 3.2 ± 1.2 mm, 16.0 ± 20.8%, and 8.24 ± 1.12, respectively. Higher mean CAVI was observed with greater mean CAL and % sites with CAL ≥ 5 mm. The mean CAVI of the healthy, localized, and generalized periodontitis groups were 8.01 ± 1.11, 8.22 ± 1.12, and 8.51 ± 1.04, respectively (p < 0.01). Linear and logistic regression analysis demonstrated a significant relationship between CAVI and all periodontal variables with β = 0.004-0.17 and OR = 1.01-1.58, respectively.

CONCLUSIONS

There is a significant dose-dependent association between the severity and extent of periodontitis and arterial stiffness measured by CAVI in Thai adults.

CLINICAL RELEVANCE

Preventing arterial stiffness, an early sign of cardiovascular events, by controlling the emerging risk factors, such as periodontitis, might have a high impact on health promotion.

503 Unlocking the mystery of haemolytic anaemia after mitral valve repair

Hemolytic anemia is an uncommon complication after mitral valve repair. All possible causes should be excluded before making a diagnosis. Echocardiography is an important tool. Transthoracic echocardiography may underestimate the severity and direction of regurgitation jets. Transesophageal echocardiography is the helpful imaging modality helping identify an accurate mechanism.

A 55-year-old female with a history of mitral valve repair 5 years earlier presented with shortness of breath for 2 months. She noticed that she had intermittent jaundice and dark urine for 5 months but these symptoms were worsening and persistent for 2 months. She had no fever and abdominal pain. She did not take any medication. The physical examination revealed mark pale conjunctiva and icteric sclera. The apex of heart was palpated at 6th intercostal space lateral to the midclavicular line. The pan-systolic murmur was audible along the mitral valve area. The lung was clear and no pedal edema. Her complete blood count showed hematocrit of 13% with fragmented red blood cell and polychromasia in a blood smear. The level of aspartate transaminase, direct bilirubin, and lactate dehydrogenase was elevated with low haptoglobin level. A chest X-ray showed cardiomegaly without pulmonary edema. The diagnosis of autoimmune hemolytic anemia was made but her symptom was not improved after corticosteroid treatment. Transthoracic echocardiography cannot explain the cause of hemolytic anemia, so the transesophageal echocardiography was performed. The echocardiography revealed severe mitral regurgitation and paravalvular leak. The turbulent flow was seen across the mitral annuloplasty ring. She underwent mitral valve replacement to treat her symptoms. After an operation, her symptoms were significantly improved without any jaundice. The hemolytic anemia was resolved.

This case demonstrated an important role of transesophageal echocardiography, especially in post heart valve surgery patient. Although hemolytic anemia after mitral valve surgery is rare, it should be considered in every hemolytic anemia patient without other explainable causes. An accurate diagnosis is a crucial role in treatment.

Abstract 503 Figure.

Arterial stiffness contributes to coronary artery disease risk prediction beyond the traditional risk score (RAMA-EGAT score)

Objectives

The traditional risk score (RAMA-EGAT) has been shown to be an accurate scoring system for predicting coronary artery disease (CAD). Arterial stiffness measured by the cardio–ankle vascular index (CAVI) is known to be a marker of atherosclerotic burden. A study was undertaken to determine whether CAVI improves the prediction of CAD beyond the RAMA-EGAT score.

Design

Cross-sectional study.

Patients

Patients with a moderate to high risk for CAD by the RAMA-EGAT score were enrolled between November 2005 and March 2006. 64-slice multidetector CT coronary angiography was used to evaluate the coronary artery calcium score and coronary stenosis. Arterial stiffness was assessed by CAVI.

Results

1391 patients of median age 59 years (range 31–88) were enrolled in the study, 635 (45.7%) men and 756 (54.3%) women. Of the 1391 patients, 346 (24.87%) had coronary stenosis. There was a correlation between CAVI and the prevalence of coronary stenosis after adjusting for traditional CAD risk factors (OR 3.29). In addition, adding CAVI into the RAMA-EGAT score (modified RAMA-EGAT score) improved the prediction of CAD incidence, increasing C-statistics from 0.72 to 0.85 and resulting in a net reclassification improvement of 27.7% (p<0.0001).

Conclusion

CAVI is an independent risk predictor for CAD. The addition of CAVI to the RAMA-EGAT score significantly improves the diagnostic yield of CAD.

Transcoronary bone marrow-derived progenitor cells in a child with myocardial infarction: first pediatric experience

BACKGROUND

Recent advances in stem cell therapy to restore cardiac function have great promise for patients with congestive heart failure after myocardial infarction in an adult population.

OBJECTIVE

We examined the benefits of bone marrow-derived progenitor cells treatment modality for the pediatric patient.

METHODS AND RESULTS

We present our first case of transcoronary autologous stem cell transplantation in a 9-year-old girl with refractory congestive heart failure secondary to myocardial infarction 1 year after transcatheter revascularization. The child received daily injections of granulocyte colony-stimulating factor for 3 days prior to the bone marrow aspiration. The bone marrow cells were isolated to constitute CD133+/CD34+ more than 90% of the total number. Subsequently, the progenitor cell suspension was injected via a transcoronary catheter without any complication. Three months after stem cell therapy, her cardiac function, assessed by both cardiac magnetic resonance and echocardiogram, has been improved with the left ventricular ejection fraction at 47% compared to the baseline of 30%.

CONCLUSION

This is the first reported pediatric case of successful transcoronary injection of bone marrow-derived progenitor cells for end-stage heart disease. The procedure is considered safe and feasible for the pediatric population.

Long-term follow-up of patients after gamma intracoronary brachytherapy failure (from GAMMA-I, GAMMA-II, and SCRIPPS-III)

We report the long-term outcome of 225 patients who failed gamma-brachytherapy for in-stent restenosis. Total adverse events, target vessel revascularization, and myocardial infarction were higher after repeat percutaneous coronary intervention versus coronary artery bypass grafting. Therefore, coronary artery bypass grafting may be the preferable first-line therapy in these patients until other therapies (i.e., drug-eluting stents) are available. Shorter time from brachytherapy to radiation failure and late thrombosis after brachytherapy were independent predictors of adverse events.

Relationship between neointimal regrowth and mechanism of acute lumen gain during the treatment of in-stent restenosis with or without supplementary intravascular radiation

We investigated whether neointimal regrowth is related to the mechanism of acute lumen gain during the treatment of in-stent restenosis (ISR) lesions both with and without adjunct intravascular brachytherapy. From the WRIST (Washington Radiation for In-Stent Restenosis Trial) cohort, 54 ISR patients ((192)Ir, 29; placebo, 25) were treated with nonrepeat stenting percutaneous interventions (excimer laser, rotational atherectomy, and/or balloon angioplasty) prior to (192)Ir or placebo therapy. Using Simpson's method, serial volumetric intravascular ultrasound (IVUS) analyses (pre- and posttreatment and 6-month follow-up) were analyzed to obtain stent, lumen, and intimal hyperplasia (IH) volumes that were then adjusted for stent length to create stent, lumen, and IH volume indexes. In the placebo group, the acute reduction of neointima (1.6 +/- 1.4 mm(3)/mm) was counteracted by intimal regrowth (2.1 +/- 1.7 mm(3)/mm). The amount of intimal regrowth correlated directly with the intimal reduction due to the intervention (r = 0.76; P < 0.001), but not with the amount of additional stent expansion. In the (192)Ir-treated group, intimal regrowth was significantly less than in the placebo group (-0.3 +/- 0.1 vs. 2.1 +/- 1.7 mm(3)/mm; P < 0.001) despite a similar initial intimal reduction (1.3 +/- 0.9 vs. 1.6 +/- 1.4 mm(3)/mm; P = NS). No correlation was found between intimal reduction at the time of the procedure and intimal regrowth in the (192)Ir group. In this study, neointimal regrowth following treatment of ISR lesions correlates directly with the extent of acute intimal volume reduction, but not with the extent of additional stent expansion. This relation is not seen in ISR segments treated with radiation, where intimal regrowth is substantially inhibited.

Late vascular response to repeat stenting for in-stent restenosis with and without radiation: an intravascular ultrasound volumetric analysis

BACKGROUND

Re-stenting of in-stent restenosis (ISR) improves acute angiographic results. Methods and Results- Volumetric intravascular ultrasound analysis was performed in 70 ISR lesions that received either placebo (n=36) or (192)Ir radiation (n=34). ISR lesions treated by re-stenting were divided into 3 groups: old stent not re-stented (A), old/new stent overlap (B), and new stent only (C). ISR lesions treated without re-stenting were categorized as D. In placebo patients, postintervention lumen volume index (LVI) was significantly greater in re-stented segments B and C than in non-re-stented segment A (P<0.05).At follow-up, however, LVI was similar in all 4 segments secondary to the increased intimal hyperplasia (IH) reaccumulation within the re-stented segments. In patients treated with (192)Ir radiation, LVI was maintained from baseline to follow-up only in non-re-stented segments A and D. Conversely, there was a significant decrease in LVI in re-stented segments B and C (P<0.05). Qualitatively, 79% of patients in the irradiated group had stent struts with undetectable neointimal versus only 27% in the placebo group (P<0.001). Coefficient of variation of IH reaccumulation was greater in re-stented segments of (192)Ir patients (B=57.3% and C=58.9%) than in re-stented segments in placebo patients (B=27.3% and C 26.8%) and non-re-stented segments in irradiated patients.

CONCLUSIONS

Additional lumen gain from re-stenting ISR lesions is counteracted by exaggerated neointimal proliferation in placebo patients. Maximum effectiveness and safety of radiation can be achieved for ISR lesions when treated without re-stenting. Thus, regardless of supplementary intravascular brachytherapy, repeat stenting strategies provided little long-term advantage.

Detection of restenosis after percutaneous transluminal coronary angioplasty using the exercise treadmill test and technetium 99m-sestamibi scintigraphy

BACKGROUND

The detection of myocardial ischemia after percutaneous transluminal coronary angioplasty (PTCA) is important because 30-50 per cent of the patients will develop restenosis within 6 months. Symptoms of chest pain and exercise stress test (EST) have shown to be less sensitive for detection of ischemia than exercise Technetium-99m Sestamibi (Tc-99m MIBI). The purpose of this study was to compare the sensitivity and specificity of chest pain, EST and Tc-99m MIBI with coronary angiography (CAG).

METHOD

Tc-99m MIBI with SPECT imaging was performed at months 1, 3 and 6 and CAG was repeated 6 months after successful PTCA. Earlier Tc-99m MIBI and CAG were performed in patients with recurrent angina pectoris or suspected restenosis.

RESULTS

Forty six patients (M 29, F 17) who had undergone successful angioplasty were prospectively enrolled. Their mean age was 61 +/- 19 yrs. Eighty eight lesions (LAD63%, LCX34%, RCA19%) were performed. Lesion characteristics were type A in 9 per cent, type in B 30 per cent and type C in 61 per cent. Fifty four per cent of PTCA were performed for single vessel disease and 46 per cent for multivessel disease. The mean duration of time between PTCA and follow-up CAG was 6.1 +/- 2.7 months. We detected restenosis from CAG in 58 per cent of the cases. The Tc-99m MIBI had higher sensitivity to detect restenosis than anginal pain (85.0% vs 39.4% p < 0.005) or EST (85.0% vs 63.6% p < 0.05) when compared with CAG. The overall accuracy of Tc-99m MIBI for the detection of restenosis was 80 per cent.

CONCLUSION

Tc-99m MIBI with SPECT imaging constitutes a better means than symptoms or exercise test to detect restenosis after successful coronary angioplasty.

Intravascular ultrasound volumetric assessment of intimal hyperplasia in stents treated with intracoronary radiation

Iridium-192 (gamma)-radiation is effective in preventing recurrent in-stent restenosis by reducing neointimal hyperplasia as illustrated by intravascular ultrasound study and plaque area-length plot. This analytic technique will further our understanding of vessel behavior to radiant energy source both inside and outside the stented coronary artery segments.