Decreased peroxisome proliferator-activated receptor gamma expression levels in pericoronary adipose tissue adjacent to atherosclerotic plaque compared to lesion-free coronary arteries

Background

Pericoronary adipose tissue (PCAT) regulates arterial homeostasis, is considered to act in paracrine manner, and plays a role in the pathogenesis of atherosclerosis. The nuclear receptor Peroxisome Proliferator-Activated receptor gamma (PPARγ) is a key regulator of adipogenesis, and alterations of its function are associated with different pathological processes related to metabolic syndrome and inflammatory response.

Purpose

To investigate whether the PCAT surrounding coronary occlusive atherosclerotic lesions shows specific PPARγ expression pattern compared to PCAT surrounding plaque-free segments

Methods

We enrolled 47 patients (32 men, aged 68±12 years old) with 3-vessel coronary artery disease (CAD) who underwent elective coronary bypass surgery. A control group of 10 age- and sex-matched patients with severe valvular disease who underwent aortic or mitral valve replacement was also included (8 men, aged 67±15 years old). PCAT samples were received from all participants. In patients with CAD, the PCAT was harvested from two sites: adjacent to an occlusive atherosclerotic coronary lesion, and a plaque-free segment. PPARγ expression levels in PCAT cells were quantified by real-time reverse transcription polymerase chain reaction.

Results

PCAT analysis showed a significant downregulation of PPARγ expression levels in CAD compared to non-CAD patients (45±19 versus 93±15, p=0.01). In addition, PPARγ levels showed significantly lower expression in PCAT from around atherosclerotic plaque compared to lesion-free sites (31±12 versus 45±19, p=0.04). Notably, the expression of PPARγ from atherosclerotic plaque showed robust negative correlations with BMI (r=−0.47, p=0.001).

Conclusions

PPARγ in PCAT surrounding coronary occlusive atherosclerotic lesions are significantly downregulated and their levels are associated with patients' BMI. Our study opens new perspectives in the pathophysiologic role of PCAT in atherosclerotic complications of diabetes and should be further investigated.

Funding Acknowledgement

Type of funding sources: None.

Detection of left ventricular hypertrophy on the ECG through machine learning with a focus on obesity

Background

Cardiac remodeling, an important aspect of cardiovascular disease (CVD) progression, is emerging as a significant therapeutic target. The electrocardiogram (ECG) is of paramount importance in the initial evaluation of a patient. However, the ECG is not a sensitive method of detecting left ventricular hypertrophy (LVH), and as far as we know, it cannot detect changes in left ventricular geometry (LVG) at early stages, especially before LVH is present. Its sensitivity is particularly low for obese patients.

Purpose

To use a machine learning (ML) classifier to detect abnormal LVG from ECG parameters/markers, even before it becomes LVH, and to propose some indicative markers useful for practitioners. We also looked at the results of our model for obese patients to test the markers in this population.

Methods

We enrolled consecutive subjects, aged 30 years or older (mean age: 61.6±12 years old) with and without essential hypertension and no indications of CVD. All patients underwent a full echocardiographic evaluation and were classified into 2 groups; those with normal geometry (NG) vs. those with concentric remodeling (CR) or LVH defined as concentric hypertrophy (CH) and eccentric hypertrophy (EH). Abnormal LVG was identified as increased relative wall thickness (RWT) and/or left ventricular mass index (LVMi). We analyzed the EKG waveforms deduced to single beat averages for each lead using custom software and extracted 70 markers. We then trained a Random Forest machine learning model to classify subjects with abnormal LVG and calculated SHAP values to perform feature importance and interaction.

Results

After screening 1120 individuals, we enrolled 594 subjects, aged 30 years or older (mean age: 61.6±12 years old). The percentage of women was 56.5%, while 71.3% of all patients were hypertensive. Hypertension, age, body mass index divided by the Sokolow-Lyon voltage (BMI/S-L), QRS-T angle, and QTc duration were among the most important parameters (Figure, left panel) identified by the model as being predictive of abnormal LVG (AUC/ROC = 0.84, sensitivity = 0.94, specificity 0.61). Specifically for obese patients, whose prevalence in our population was 60.3%, our model performed well (sensitivity = 0.71, specificity = 0.92. When we tried our model without the the BMI/S-L parameter, the specificity dropped to 0.88. We also found that a cut-off point of 18 for the BMI/S-L marker predicted the patients who were more probable to have developed abnormal LVG.

Conclusions

This study is the first to demonstrate the promising potential of ML modeling for the efficient and cost-effective diagnostic screening of abnormal LVG and cardiac remodeling through ECG. We found specific clinical and ECG parameters that can predict early pathological changes of LVG in patients without established CVD and detect the population who will benefit from a detailed echocardiographic evaluation.

Funding Acknowledgement

Type of funding sources: None.

Ventricular activation time as a marker for complex ventricular arrhythmias, sudden cardiac death and ICD implantation in hypertrophic cardiomyopathy

Background

Identification of patients with hypertrophic cardiomyopathy (HCM) who are at high risk of sudden cardiac death (SCD) is essential, as life-threatening ventricular arrhythmias (VAs) can be effectively prevented with an implantable cardioverter defibrillator (ICD). Risk stratification using HCM Risk-SCD score is recommended in the 2014 ESC guidelines for the management of patients with HCM. However, the role of electrocardiogram (ECG) in risk stratification is less well established.

Purpose

We investigated the association between the ventricular activation time (VAT), an ECG marker of the duration of ventricular depolarization, with the HCM Risk-SCD score, the presence of complex VAs, the implantation of an ICD and ICD-therapy for VAs.

Methods

Patients with a history of HCM, documented by echocardiography, were studied. The 12-lead ECG and echocardiography were performed on the same day. On ECG, we evaluated the VAT in milliseconds, between the onset of the QRS complex to the peak of R wave on V5 or V6 precordial ECG leads. A careful personal and family history for unexplained syncope and SCD was obtained, respectively. The presence of non-sustained ventricular tachycardia (NSVT) and ICD therapy were assessed either with 48h ECG recording or ICD interrogation. HCM Risk-SCD score was calculated by the corresponding ESC online calculator. Statistical analysis was performed using the SPSS software.

Results

Thirty-three patients with HCM were included (mean age 51±12 years, 78.8% male). According to the HCM Risk-SCD score, HCM patients were divided into three groups: low-risk (<4, 45.5%), intermediate-risk (4 to <6, 24.2%) and high-risk (>6, 30.3%) for SCD. Approximately half of the HCM patients had episodes of NSVT (48.5%) and an ICD (48.5%). Ventricular activation time was significantly prolonged in high-risk group compared either with intermediate-risk (74±24.5 vs 48.7±16.4, p=0.006) or low-risk (74±24.5 vs 44.3±12.6, p<0.001). HCM patients with NSVT had a significantly prolonged VAT compared with those without NSVT (62.19±25.2 vs 47.06±15.3, p=0.022). Moreover, HCM patients with an ICD had a higher VAT than those without an ICD (62.1±25.2 vs 47±15.3, p=0.003). VAT was also significantly prolonged in the group with appropriate ICD therapy for VAs compared with that without ICD therapy (82.8±22.1 vs 52.2±16.4, p=0.007). Finally, there was a significant positive correlation between VAT and NSVT (r=0.352, p=0.044), history of syncope (r=0.604, p<0.001), HCM risk-SCD score (r=0.493, p=0.004), ICD implantation (r=0.508, p=0.003) and ICD therapy (r=0.648, p=0.007) for VAs while there was not a correlation with the family history of SCD.

Conclusion

Prolongation of VAT is associated with NSVT, HCM risk score for SCD, ICD implantation and ICD therapy for VAs in patients with HCM and it seems to be a novel, easy to measure, ECG marker for risk stratification.

Funding Acknowledgement

Type of funding sources: None.

Differences in microRNA expression in pericoronary tissue adjacent to atherosclerotic plaque and from lesion-free coronary artery

Background

Pericoronary adipose tissue (PCAT) plays a key role in the pathogenesis of atherosclerosis. PCAT is a source of microRNAs (miRs) that acts as messengers for intercellular communication. In this study, we investigated whether the PCAT surrounding coronary occlusive atherosclerotic lesions shows specific miR expression patterns compared to PCAT surrounding plaque-free segments.

Purpose

To evaluate the expression of miRs that are known to be implicated in the pathophysiology of atherosclerosis.

Methods

We included 49 patients (38 men, age 65±9 years) with 3-vessel coronary artery disease, who underwent elective coronary bypass surgery. The PCAT was harvested from two sites: adjacent to an occlusive atherosclerotic coronary lesion, and a plaque-free segment. miR-133a, miR-21, miR-26b, miR-9 and miR-143 levels in PCAT cells were quantified by real-time reverse transcription polymerase chain reaction.

Results

miR-26b, miR-21 and miR-143 showed significantly greater expression in PCAT samples taken from around atheromatous plaque (154±295 versus 37±96, p=0.014, for miR-26b; 122±265 versus 29±79, p=0.014, for miR-21; and 181±356 versus 31±50, p=0.03, for miR-143) (Figure 1). In addition, the expression of miR-143, miR-26b and miR-21 in PCAT from atherosclerotic plaque showed robust positive correlations with body.mass index (r=0.451, p=0.001, r=0.41, p=0.03 and r=0.416, p=0.003 respectively),

Conclusions

Analysis of PCAT located in proximity to atherosclerotic plaque showed a different pattern of miR expression compared to PCAT in a plaque-free segment. Our findings open new perspectives for the role of PCAT in the pathophysiological mechanisms of atherosclerotic disease and should be further investigated.

Funding Acknowledgement

Type of funding sources: None.

Artificial intelligence-based opportunistic screening for the detection of arterial hypertension through ECG signals

Background

Hypertension is a major risk factor for cardiovascular disease (CVD) which often escapes the diagnosis or should be confirmed by several office visits. The electrocardiogram (ECG) is one of the most widely used diagnostic tools and could be of paramount importance in patients' initial evaluation.

Purpose

To detect whether a person is hypertensive using features from the ECG, as well as basic anthropometric features such as age, sex, and body mass index (BMI).

Methods

We used machine learning (ML) techniques based features derived from the electrocardiogram for detecting hypertension in a population without CVD. We enrolled 1091 subjects who were classified into hypertensive and normotensive group. We trained 3 ML models, specifically logistic regression, k-nearest-neighbors, and random forest (RF), to predict the existence of hypertension in patients based only on a few basic clinical parameters and ECG-derived features. We also calculated Shapley additive explanations (SHAP), a sophisticated feature importance analysis, to interpret each feature's role in the random forest's predictions.

Results

Our RF model was able to distinguish hypertensive from normotensive patients with accuracy 84.2%, specificity 66.7%, sensitivity 91.4%, and area under the receiver-operating curve 0.86. Age, BMI, BMI-adjusted Cornell criteria (BMI multiplied by RaVL+SV3), R wave amplitude in aVL, and BMI-modified Sokolow-Lyon voltage (BMI divided by SV1+RV5), were the most important anthropometric and ECG-derived features in terms of the success of our model. Figure 1 shows the results in detecting hypertension by the Random Forest.

Conclusions

Our ML algorithm is effective in the detection of hypertension in patients using ECG-derived and basic anthropometric criteria. Our findings open new horizon in the detection of many undiagnosed hypertensive individuals who have an increased cardiovascular disease risk.

Funding Acknowledgement

Type of funding sources: None.

Elevated platelet reactivity in patients with uncontrolled hypertension: the effect of CHA2DS2-VASc score

Background

Hypertension is associated with vascular and endothelial dysfunction that may result in a greater propensity for reactive platelets to cause thrombosis.

Purpose

The aim of this study was to evaluate multiple platelet activation pathways in hypertensive patients with different level of blood pressure control and cardiovascular risk factors.

Methods

Thirty nine uncontrolled (office BP >140/90 mmHg and ambulatory daytime BP >135/85 mmHg, 27 males, aged 58±9 years) and 32 well controlled (office BP <140/80 mmHg and ambulatory daytime BP <135/85 mmHg, 21 males, aged 58±8 years) essential hypertensive patients were included in the study. Twenty four healthy individuals (12 males, aged 53±10 years) were served as control group. Blood samples were obtained before and 48 hours after the procedure and platelet aggregation was tested in platelet rich plasma after activation with arachidonic acid (AA), adenosine diphosphate ADP), collagen (Col), epinephrine (Epi) and ristocetin (Risto), by using AggRAM Platelet Aggregation Analyzer.

Results

Hypertensive patients showed elevated platelet reactivity in all platelet activation pathways compared to normotensive group (AA: 88.8±6.8% versus 79.5±7.3%, ADP: 86.8±9.1% versus 71.5±7.7%, Col: 86.5±5.7% versus 73.9±6.7%, Epi: 92.6±5.4% versus 80.5±5.7%, Risto: 93.8±6.8% versus 79.9±6.3%, p<0.05 for all). Col, Epi and Risto platelet activation pathway showed a statistically significant increase in patients with uncontrolled hypertension compared to the group with well controlled hypertension (AA: 88.8±6.1% versus 89.1±4.1%, ADP: 89.8±4.1% versus 87.5±4.7%, Col: 87.5±4.7% versus 81.9±6.7%, Epi: 93.6±4.4% versus 80.1±5.7%, Risto: 94.8±3.8% versus 80.9±4.3%,). Notably, strong correlations were found between the Col platelet pathway activation and Risto platelet pathway activation and CHA2DS2-VASc score (r=0.57, p<0.001 and r=0.61, p<0.001, respectively) in hypertensive patients.

Conclusions

Patients with uncontrolled hypertension showed elevated platelet reactivity. Patients with high CHA2DS2-VASc even without atrial fibrillation carry also a higher risk of thrombosis as indicated by the increased platelet aggregation under certain pathways of activation.

Funding Acknowledgement

Type of funding sources: None.

Usefulness of right ventricular longitudinal systolic strain to predict the progression to heart failure with preserved ejection fraction in hypertensive patients

Background

Accurate assessment of right ventricular (RV) systolic function is important, as it is an established prognostic marker in cardiac diseases. Speckle-tracking echocardiography is a sensitive tool for detection of subclinical left ventricular impairment in essential hypertension.

Purpose

Our aim was to investigate the usefulness of RV longitudinal peak systolic strain (LS) to predict the risk of future development of heart failure with preserved ejection fraction (HFpEF) in patients with essential hypertension

Methods

We performed a retrospective observational study that included 453 patients with essential hypertension (266 males, aged 63±18 years) and 175 normotensives (100 males, aged 66±15 years). Standard echocardiography was performed at the initial visit. 2D speckle tracking echocardiography with evaluation of longitudinal strain in each segment of the RV (basal: RVLS-B; mid: RVLS-M, apical: RVLS-A) and global RV free-wall strain (RVLS-G) were also performed. We studied the cases of new onset HFpEF in hypertensive patients.

Results

The median follow up was 85 months (22–122). RVLS-G, RVLS-B and RVLS-M were significantly impaired in hypertensives compared to controls (RVLS-G: −16.1±9.7 vs −20.0±5.1, RVLS-B: −11.7±3.7 vs −20.6±3.3, RVLS-M:-16.3±5.4 vs −20.7±4.9, p<0.05 for all). No significant difference was detected for the RVLS-A (−20.1±3.8 for hypertensives vs −21.31±6.5 for controls, p=NS). Thirty two hypertensive patients developed HFpEF (7%). A cut-off RVLS-G worse than −17% was significantly associated with new onset HFpEF (p<0.001) in those patients. A multivariate Cox regression analysis showed that RVLS-G had independent significant prognostic value for the risk of HFpEF (HR: 10.5, 95% confidence interval (CI): 7.3–25.4).

Conclusions

Essential hypertension leads to a decrease of RVLS which is strong predictor of a new onset HFpEF. Future studies are needed to assess the significance of these findings and the effect of treatment.

Funding Acknowledgement

Type of funding sources: None.

P-wave duration and atrial fibrillation recurrence after catheter ablation, a systematic review and meta-analysis

Funding Acknowledgements

Type of funding sources: None.

Background

Atrial fibrillation (AF) is a global health problem with high morbidity and mortality. Catheter ablation (CA) can reduce AF burden and symptoms, but AF recurrence (AFr) remains an issue. Simple AFr predictors like P-wave duration (PWD) could help improve AF therapy.

Purpose

This updated meta-analysis reviews the increasing evidence for the association of AFr with PWD and offers practical implications.

Methods

Publication databases were systematically searched and cohort studies reporting PWD and/or morphology at baseline and AFr after CA were included. Complete interatrial block (cIAB) was defined as PWD≥120 ms and biphasic morphology in inferior leads. Random-effects analysis was performed using the Review Manager 5.3 and R programs after study selection, quality assessment and data extraction, to report odds ratio (OR) and confidence intervals (CI).

Results

Among 4175 patients in 22 studies, 1138 (27%) experienced AFr. Patients with AFr had longer PWD with a mean pooled difference of 7.8 ms (19 studies, p<0.001)(Figure 1). Pooled OR was 2.04 (1.16-3.58) for PWD>120 ms (13 studies, p=0.01), 2.42 (1.12-5.21) for PWD>140 ms (2 studies, p=0.02), 3.97 (1.79-8.85) for cIAB (6 studies, p<0.001) and 10.89 (4.53-26.15) for PWD>150 ms (2 studies, p<0.001)(Figure 2). There was significant heterogeneity but no publication bias detected.

Conclusion

PWD is an independent predictor for AF recurrence after LA ablation. The AFr risk is increasing exponentially with PWD prolongation. This could facilitate risk-stratification by identifying high-risk patients (cIAB, PWD>150 ms) and adjusting follow-up or interventions.

Right ventricular longitudinal systolic strain can predict new onset heart failure with preserved ejection fraction in hypertensive patients

Funding Acknowledgements

Type of funding sources: None.

Purpose

Accurate assessment of right ventricular (RV) systolic function is important, as it is an established prognostic marker in cardiac diseases. Speckle-tracking echocardiography is a sensitive tool for detection of subclinical left ventricular impairment in essential hypertension. We associated RV function using longitudinal peak systolic strain (GLS) in patients with essential hypertension with the risk of future development of heart failure with preserved ejection fraction (HFpEF).

Methods

 We performed a retrospective observational study that included 458 patients with essential hypertension (266 males, aged 63 ± 18 years) and 179 normotensives (100 males, aged 66 ± 15 years). Standard echocardiography was performed at the initial visit. 2D speckle tracking echocardiography with evaluation of longitudinal strain in each segment of the RV (basal:  RVLS-B; mid: RVLS-M, apical: RVLS-A) and global RV free-wall strain (RVLS-G) were also performed. We studied the cases of new onset HFpEF in hypertensive patients. 

Results

The median follow up was 85 months (22–122). RVLS-G, RVLS-B and RVLS-M were significantly impaired in hypertensives compared to controls (RVLS-G: -16.1 ± 9.7 vs -20.0 ± 5.1, RVLS-B: -11.7 ± 3.7 vs -20.6 ± 3.3, RVLS-M:-16.3 ± 5.4 vs -20.7 ± 4.9, p < 0.05 for all). No significant difference was detected for the RVLS-A (-20.1 ± 3.8 for hypertensives vs -21.31 ± 6.5 for controls, p = NS). Thirty two hypertensive patients developed HFpEF (7 %). A cut-off RVLS-G worse than -17 % was significantly associated with new onset HFpEF (p< 0.001) in those patients. A multivariate Cox regression analysis showed that RVLS-G had independent significant prognostic value for the risk of HFpEF (HR: 10.5, 95% confidence interval (CI): 7.3-25.4). 

Conclusions

Essential hypertension leads to a decrease of RVLS which is strong predictor of a new onset HFpEF. Future studies are needed to assess the significance of these findings and the effects of treatment.

Prediction of abnormal left ventricular geometry on the ECG through machine learning with a focus on obesity

Background

Cardiac remodeling, an important aspect of cardiovascular disease (CVD) progression, is emerging as a significant therapeutic target. However, the ECG is not a sensitive method of detecting left ventricular hypertrophy (LVH), and as far as we know, it cannot detect changes in left ventricular geometry (LVG) at early stages, especially before LVH is present. Its sensitivity is particularly low for obese patients.

Purpose

To use a machine learning (ML) classifier to detect abnormal LVG from EKG parameters/markers, even before it becomes LVH, and to propose some indicative markers useful for practitioners. We also looked at the results of our model for obese patients to test the markers in this population.

Methods

We enrolled 594 consecutive subjects, aged 30 years or older (mean age: 61.6±12 years old) with and without essential hypertension and no indications of CVD. We tried to build a “clean” dataset through which we can target the clinical, anthropometric, and electrocardiogram measurements indicative of abnormal LVG. All patients underwent a full echocardiographic evaluation and were classified into 2 groups; those with normal geometry (NG) vs. those with concentric remodeling (CR) or LVH. Abnormal LVG was identified as increased relative wall thickness (RWT) and/or left ventricular mass index (LVMi). We analyzed the EKG waveforms deduced to single beat averages for each lead using custom software and extracted 70 markers. We then trained a Random Forest machine learning model to classify subjects with abnormal LVG and calculated SHAP values to perform feature importance and interaction.

Results

The percentage of women was 56.5%, while 71.3% of all patients were hypertensive. Hypertension, age, body mass index divided by the Sokolow-Lyon voltage (BMI/S-L), QRS-T angle, and QTc duration were among the most important parameters (Figure, left panel) identified by the model as being predictive of abnormal LVG (AUC/ROC = 0.84, sensitivity = 0.94, specificity 0.61). Specifically for obese patients, whose prevalence in our population was 60.3%, our model performed well (sensitivity = 0.71, specificity = 0.92. When we tried our model without the the BMI/S-L parameter, the specificity dropped to 0.88. We also found that a cut-off point of 18 for the BMI/S-L marker predicted the patients who were more probable to have developed abnormal LVG (Figure 1).

Conclusions

This study is the first to demonstrate the promising potential of ML modeling for the efficient and cost-effective diagnostic screening of abnormal LVG through ECG. We found specific clinical and ECG parameters that can predict early pathological changes of LVG in patients without established CVD and detect the population who will benefit from a detailed echocardiographic evaluation. Our model contributes to the development of human-centered and autonomous technologies and can optimize patient-management and treatment.

Funding Acknowledgement

Type of funding sources: None. Figure 1

MicroRNA profile analysis in pericoronary adipose tissue of diabetic patients with significant coronary artery disease

Background

Pericoronary adipose tissue (PCAT) regulates arterial homeostasis, is considered to act in paracrine manner,and plays a role in the pathogenesis of atherosclerosis. PCAT may be a source of microRNAs (miRs) that target other tissues and act as messengers for intercellular communication. In this study, we investigated whether the PCAT surrounding coronary occlusive atherosclerotic lesions shows specific miRs expression patterns in patients with diabetes type 2 compared to non-diabetic patients.

Methods

We enrolled 43 patients (29 men, aged 63±12 years old) with 3-vessel coronary artery disease who underwent elective coronary bypass surgery with and without diabetes type 2. The PCAT samples were received from all participants. miR-133a, miR-21, miR-26b, miR-9 and miR-143 expression levels in PCAT cells were quantified by real-time reverse transcription polymerase chain reaction.

Results

Twenty-one patients with diabetic type 2 (14 men, 64±10 years old) and twenty=two non-diabetic patients (15 men, 62±15 years old) were included in the study. PCAT analysis showed a significant upregulation of miR-21 levels in diabetic compared to non-diabetic patients (181±76 versus 21±15, p=0.04). Diabetic patients also revealed a significant increase of miR-26b and miR-143 expression in PCAT samples compared to on-diabetics (33±22 versus 16±13, p=0.02, 93±42 versus 16±23, p=0.01). No significant differences between the two sites were observed in PCAT expression of miR-133a and miR-9 (73±12 versus 130±143, 56±44 versus 34±33, respectively, p =NS for both).

Conclusions

miRs expression in PCAT from diabetic patients with significant coronary disease show a distinct expression profile. Our study opens new perspectives in the pathophysiologic role of PCAT in atherosclerotic complications of diabetes and should be further investigated.

Funding Acknowledgement

Type of funding sources: None.

Long term prognostic value of myocardin expression levels in non-ischemic dilated cardiomyopathy

Background

We The mortality of patients with non-ischemic dilated cardiomyopathy (NIDCM) remains substantial. We evaluated gene expression levels of myocardin, an early cardiac gene, in the peripheral blood cells of NIDCM patients as a prognostic biomarker in their long-term outcome and mortality from congestive HF (CHF).

Methods

We retrospectively analyzed 101 consecutives optimally treated NIDCM patients of Cretan origin who were enrolled from the HF clinic of our hospital from November 2005 to December 2008. Our patient data were either taken from their medical files or recorded during visits to the HF unit or hospitalizations. Follow-up was carried out by telephone interview and by accessing information from general practitioners and cardiologists in private practice.

Results

The median follow up period was 8 years (mean follow-up 7±3.4 years). The overall mortality during follow-up was 61.4%, while mortality due to congestive heart failure (CHF) was 49.5%. Higher CHF and all-cause mortality were observed in patients with myocardin levels >14.26 (p<0.001 for both CHF and all-cause mortality). A multivariate Cox regression analysis showed that myocardin level of expression had independent significant prognostic value for the risk of death from CHF (HR: 14.5, 95% confidence interval (CI): 5.3–39). in those patients.

Conclusions

Peripheral blood cells gene expression of myocardin, an early myocardial marker, may serve as prognostic biomarkers of the long-term outcome of patients with NIDCM. Our findings open new prospects in the risk stratification of these patients.

Funding Acknowledgement

Type of funding sources: None. Figure 1

Right ventricular longitudinal systolic strain as a predictor of new onset heart failure with preserved ejection fraction in hypertensive patients

Purpose

Accurate assessment of right ventricular (RV) systolic function is important, as it is an established prognostic marker in cardiac diseases. Speckle-tracking echocardiography is a sensitive tool for detection of subclinical left ventricular impairment in essential hypertension. We associated RV function using longitudinal peak systolic strain (GLS) in patients with essential hypertension with the risk of future development of heart failure with preserved ejection fraction (HFpEF).

Methods

We performed a retrospective observational study that included 452 patients with essential hypertension (266 males, aged 63±18 years) and 175 normotensives (100 males, aged 66±15 years). Standard echocardiography was performed at the initial visit. 2D speckle tracking echocardiography with evaluation of longitudinal strain in each segment of the RV (basal: RVLS-B; mid: RVLS-M, apical: RVLS-A) and global RV free-wall strain (RVLS-G) were also performed. We studied the cases of new onset HFpEF in hypertensive patients.

Results

The median follow up was 85 months (22–122). RVLS-G, RVLS-B and RVLS-M were significantly impaired in hypertensives compared to controls (RVLS-G: −16.1±9.7 vs −20.0±5.1, RVLS-B: −11.7±3.7 vs −20.6±3.3, RVLS-M: −16.3±5.4 vs −20.7±4.9, p<0.05 for all). No significant difference was detected for the RVLS-A (−20.1±3.8 for hypertensives vs −21.31±6.5 for controls, p=NS). Thirty two hypertensive patients developed HFpEF (7%). A cut-off RVLS-G worse than −17% was significantly associated with new onset HFpEF (p<0.001) in those patients. A multivariate Cox regression analysis showed that RVLS-G had independent significant prognostic value for the risk of HFpEF (HR: 10.5, 95% confidence interval (CI): 7.3–25.4).

Conclusions

Essential hypertension leads to a decrease of RVLS which is strong predictor of a new onset HFpEF. Future studies are needed to assess the significance of these findings and the effects of treatment.

Funding Acknowledgement

Type of funding sources: None.

Differential microRNAs profile analysis in pericoronary adipose tissue adjacent to atherosclerotic plaque

Background

Pericoronary adipose tissue (PCAT) regulates arterial homeostasis, is considered to act in paracrine manner, and plays a role in the pathogenesis of atherosclerosis. PCAT may be a source of microRNAs (miRs) that target other tissues and act as messengers for intercellular communication. In this study, we investigated whether the PCATsurrounding coronary occlusive atherosclerotic lesions shows specific miRs expression patterns compared to PCAT surrounding segments without significant atherosclerosis (plaque-free segments). We evaluated expression of miRs that are known to be implicated in the pathophysiology of atherosclerotic disease.

Methods

We included 40 patients (38 men, aged 62±12 years old) with 3-vessel coronary artery disease who underwent elective coronary bypass surgery. The PCAT was harvested from two sites: adjacent to coronary occlusive atheroscleroticlesion and plaque-free segment. miR-133a, miR-21, miR-26b, miR-9 and miR-143 expression levels in PCAT cells were quantified by real-time reverse transcription polymerase chain reaction.

Results

PCAT analysis revealed a significant downregulation of miR-133a levels in periplaque samples compared to those that were not adjacent to atheroscrerotic plaque (35.4±4.3 versus 87.2±130.5, p=0.03). We also found a significant decrease of miR-143 expression in segments adjacent to plaque compared to those surrounding plaque-free coronary artery (72.6±14.3 versus 213.2±222.5, p=0.01). No significant differences between the two sites were observed in PCAT expression of miR-21, miR-26b, miR-9 (170.7±205 versus 130.9±303.2, 129.8±64.3 versus 200.2±330.6, 40±0.2 versus 30.2±3.6, respectively, p=NS for all).

Conclusions

miR-133a and miR-143 expression in PCAT surrounding coronary occlusive atherosclerotic lesions were significantly downregulated compared to PCAT surrounding segments without significant atherosclerosis. Our study opens new perspectives in the role of PCAT in the pathophysiological mechanisms and the treatment of atherosclerotic disease and should be further investigated.

Funding Acknowledgement

Type of funding sources: None.

Occult aorto-iliac disease in patients with symptomatic coronary artery disease

BACKGROUND

Atherosclerosis may affect the entire cardiovascular system despite absence of symptoms. Early changes in the wall of the carotid artery have been related to a higher morbidity and mortality from coronary artery disease (CAD). This study was conducted to investigate the relationship between the presence of occult aorto-iliac disease (OAID) and certain risk factors with the severity of CAD.

METHODS

Two hundred and eighty-four consecutive patients subjected to coronary angiography (CA) were studied. Additional images of the aorto-iliac arterial segment were taken. Patients with negative CA or symptomatic lower limb arterial disease (LLAD) were excluded from further analysis. In the remaining patients, the risk factors (age, smoking, diabetes mellitus, hypertension, hyperlipidemia and positive family history for atherosclerosis) and the severity of coronary artery disease (CAD) were analyzed in relation to the presence or absence of OAID.

RESULTS

Twelve patients with impaired renal function were excluded from the study. Negative CA was found in 12% (32/272) and symptomatic LLAD was present in 14% (37/272). Eligible for further analysis were 203 patients with positive CA and no LLAD. A hundred and ten of them had a positive CA and the presence of OAID whereas the remaining 93 patients had only a positive CA. The patients with OAID had more severe CAD on CA (p=0.003). There was no difference between the two groups concerning age and gender. The most common risk factors in both groups were hypercholesterolemia and a positive family history but with a significantly higher prevalence in the patients with OAID (p=0.008 and p<0.001, respectively).

CONCLUSIONS

The presence of OAID in coronary patients was associated with more severe CAD and with a significantly higher prevalence of hypercholesterolemia and positive family history for atherosclerosis. This subset of patients may represent those with more aggressive atherosclerosis.

The influence of premedication on heart rate variability

Analysis of heart rate variability has been used to study the effects of midazolam, morphine and clonidine on the autonomic nervous system, when administered to patients for premedication. Ninety-five patients were studied 60 min before and 60 min after premedication. Normal saline (n = 25), midazolam 0.08 mg.kg-1 (n = 24), morphine 0.15 mg.kg-1 (n = 23), or clonidine 2 micrograms.kg-1 (n = 23) were administered intramuscularly by random allocation. A Holter device was connected to the patient during the study period. Using power spectral analysis the low-frequency and high-frequency components were calculated from the Holter recordings. These are markers for sympathetic and parasympathetic activity respectively; the low- to high-frequency ratio was also calculated, a ratio of > 1 signifying sympathetic dominance. A significant reduction was noticed in both low-frequency and high-frequency power in the three premedicated groups, whereas no changes were observed in the normal saline group. In the case of midazolam, both the low and high frequencies were decreased but the low- to high-frequency ratio did not change significantly. Morphine and clonidine depressed the low-frequency component more than the high-frequency component and the low- to high-frequency ratio was decreased, suggesting parasympathetic dominance. We conclude that heart rate variability may be a useful tool for investigating the effect of drugs on the autonomic nervous system.

Incidence of ventricular arrhythmias during silent myocardial ischaemia in coronary artery disease

This study investigated the relationship between silent myocardial ischaemia during daily life and ventricular ectopic activity in patients with angiographically confirmed coronary artery disease and preserved left ventricular function. We studied 45 patients (37 men, 8 women, aged 42-70 years) who satisfied the above criteria. All underwent 72-h continuous electrocardiographic monitoring for the detection of silent ischaemic episodes and ventricular arrhythmias. A total of 225 ischaemic episodes were recorded, of which 198 (88%) were silent. Fourteen of the silent episodes (7.1%) were associated with ventricular arrhythmias. There was no statistically significant relationship between the association of silent ischaemia with arrhythmias and the patients' exercise test or angiography findings. However, the ventricular arrhythmias tended to be associated with ischaemic episodes of longer duration and with greater maximum ST-segment depression. Silent myocardial ischaemia during everyday activity is accompanied by ventricular ectopic activity in only a small percentage of cases. The association between ischaemia and ventricular arrhythmias seems to have more to do with the duration of the ischaemic episode and the degree of ST segment depression than with the severity of the underlying coronary artery disease.

Impact of atrioventricular delay on heart rate variability of paced patients with and without heart failure

The aim of the study was to investigate whether the optimisation of atrioventricular (AV) delay in patients with complete AV block, with or without heart failure, paced under VDD mode, has an effect on heart rate variability and consequently on the autonomic nervous system in these patients. We studied 10 patients (Group I: 7 men, aged 68 +/- 9 years) with normal left ventricular function and 9 patients (Group II: 6 men, aged 70 +/- 6 years) with systolic left ventricular dysfunction (NYHA heart failure Class II or III). Each patient was paced for 24 h with the optimal and 24 h with the worst AV delay in random order and ambulatory electrocardiograms (ECGs) (Marquette) were recorded. Spectral heart rate variability was analysed for each 24-h period on a Holter analysis system (Marquette Series 8000). The optimal and worst AV delay were determined by echo-Doppler as those which produced the greatest and least cardiac output, respectively. For the patients in Group I, there was no difference between the two AV delays as regards indices of heart rate variability. In contrast, for Group II the total frequency (TF) was significantly higher and the low frequency (LF) and LF/high frequency (HF) ratio were significantly lower when the patients were paced with optimum AV delay. Furthermore, this AV delay resulted in significantly higher mean NN and SD. In conclusion, in patients with normal left ventricular function, changes in AV delay do not appear to affect the activity of the autonomic nervous system in the heart. In patients with mild to moderate heart failure, optimisation of the AV delay causes a significant drop in sympathetic nervous tone.

Intraindividual reproducibility of heart rate variability before and during postural tilt in patients with syncope of unknown origin

Fast Fourier analysis (FFT) of heart rate may be used to characterize overall heart rate variability (HRV) as well as low (LF: 0.06-0.10 Hz) and high (HF: 0.15-0.40 Hz) frequency components, which are attributable to sympathetic and vagal influences. This study examined the reproducibility of the spectral characteristics of HRV before and during postural tilt in patients being evaluated for unexplained syncope. Twenty patients (14 men, age 55 +/- 12 years) with a history of syncopal episodes underwent 2 tilt table tests (T1 and T2) 1 to 6 weeks apart. For purposes of analyses the patients were divided into 2 groups according to the results of tilt testing. In 11 patients (Group A: 7 men, mean age 53.5 +/- 12 years) syncope was induced in 1 (5 patients) or both tilt tests. In the remaining 9 patients (Group B: 7 men, age 56.7 +/- 14 years) syncope did not develop during either test. Spectral indexes (SI) of HRV were computed by FFT for 2-minute segments derived from Holter recordings before and during 60 degrees head-up tilt. We compared the SI measured in the two tilt tests during the following 2-minute periods: P1, just before tilt at rest, in a supine position; P2, immediately after tilt; P3, just before the end of the tilt.

RESULTS

P1 and P2: There were no significant differences in SI between T1 and T2 for low frequencies, high frequencies, or total power in either Group. In Group A, LF at time of maximum tilt exposure (P3) tended to be slower during T2 than in T1 (5.58 +/- 1.44 vs. 6.56 +/- 1.11, P < 0.05). However, this difference primarily reflects the findings in the five patients in whom syncope did not occur during T2. When these 5 patients were excluded the LF were essentially identical (6.43 +/- 0.97 vs 6.80 +/- 1.30; P = NS).

CONCLUSIONS

Spectral indexes of HRV before and during the early part of tilt testing are reproducible. The SI during the later part of the test are related to the patient's response. However, this response is not predictable on the basis of sympathetic or parasympathetic tone before or during the early part of the test.