Electrophysiological effects of late percutaneous coronary intervention for infarct-related coronary artery occlusion: the Occluded Artery Trial-Electrophysiological Mechanisms (OAT-EP)

Association of revascularization with risk of ventricular arrhythmias in patients with chronic total occlusion of coronary arteries: Systematic review and meta-analysis

BACKGROUND

Coronary chronic total occlusion (CTO) can result in ischemic cardiomyopathy which may create substrate supportive of ventricular arrhythmias (VA). The purpose of this meta-analysis is to evaluate the association of CTOs with risk of ventricular arrhythmias (VAs) and to assess the utility of CTO percutaneous coronary intervention (PCI) in this setting.

METHODS

A literature search was conducted for studies reporting an association between CTOs and VAs and PCI VAs among patients with CTO. VAs were defined as ventricular tachycardia, ventricular fibrillation, sudden cardiac death, and appropriate implantable cardiac defibrillator therapy. The search included the following databases: Ovid MEDLINE, EMBASE, Web of Science, and Google Scholar. The search was not restricted to time or publication status.

RESULTS

Nine studies with 3068 participants (1405 with CTOs and 1663 with coronary artery disease [CAD]) met inclusion criteria. CTOs were associated with significantly higher risk of VAs compared with patients with CAD without CTOs (OR 2.25, 95 % CI 1.92-2.64; p < 0.01). Three studies with 1830 patients with CTOs (970 revascularized, 860 on optimal medical therapy) met inclusion criteria for evaluating the association of CTO revascularization and VAs. CTO PCI was associated with a significantly lower risk of VAs compared with patients treated with optimal medical therapy.

CONCLUSIONS

Patients with CTOs appear to have a higher burden of VAs compared with patients with CAD without CTOs. Revascularization of CTOs was found to be associated with significant reduction in risk of VAs, however additional high-quality studies are required to further evaluate this association.

Symptom-to-balloon time and risk of ventricular arrhythmias in patients with STEMI undergoing percutaneous coronary intervention: The VERY-STEMI study

Background

Ventricular arrhythmias (VAs) mainly occur in the early post-myocardial infarction (MI) period. However, studies examining the association between total myocardial ischemia time interval and the risk of new-onset VAs during a long-term follow-up are scarce.

Methods

This study (symptom-to-balloon time and VEntricular aRrhYthmias in patients with STEMI, VERY-STEMI study) was a multicenter, observational cohort and real-world study, which included patients with ST-segment elevation MI (STEMI) undergoing percutaneous coronary intervention (PCI). The primary endpoint was cumulative new-onset VAs during follow-up. The secondary endpoints were the major adverse cardiovascular events (MACE) and changes in left ventricular ejection fraction (ΔLVEF, %).

Results

A total of 517 patients with STEMI were included and 236 primary endpoint events occurred. After multivariable adjustments, compared to patients with S2BT of 24 h-7d, those with S2BT ≤ 24 h and S2BT > 7d had a lower risk of primary endpoint. RCS showed an inverted U-shaped relationship between S2BT and the primary endpoint, with an S2BT of 68.4 h at the inflection point. Patients with S2BT ≤ 24 h were associated with a lower risk of MACE and a 4.44 increase in LVEF, while there was no significant difference in MACE and LVEF change between the S2BT > 7d group and S2BT of 24 h-7d group.

Conclusions

S2BT of 24 h-7d in STEMI patients was associated with a higher risk of VAs during follow-up. There was an inverted U-shaped relationship between S2BT and VAs, with the highest risk at an S2BT of 68.4 h.

Study on the mechanism of anti-MIRI action of total flavones of Fructus Chorspondiatis by PET/CT imaging

Background

To investigate anti myocardial ischemia/reperfusion injury (MIRI) action of total flavones of Fructus Chorspondiatis (TFFC) in rats by ¹³N-ammonia micro PET/CT imaging, etc.

Methods

Male Sprague-Dawley rats were randomly divided into 6 groups. Micro PET/CT imaging was performed before and after modeling to calculate the volume (VOI) and SUV_mean of myocardial ischemic area. The oxidative stress index [(superoxide dismutase (SOD), malondialdehyde (MDA)] and the marker enzymes [creatine kinase (CK), lactate dehydrogenase (LDH)] of myocardial injury were detected. The pathological changes of myocardial were observed via HE staining. A MIRI model of rat cardiomyocytes in vitro was established, the damage and apoptosis of myocardial cells in each group were observed, and the apoptosis rate of cardiomyocytes was detected.

Results

The imaging viscosities of the imaging agents were observed at 24 and 48 h in each group. The VOI of 24 h imaging was (6.33±2.02), (6.01±1.56) and (3.32±0.86) mm³, respectively. The VOI of 48 h imaging was (3.31±1.33), (2.61±1.01) and (1.32±0.58) mm³. The 72 h imaging medium and high dose group recovered, while the low dose group still saw sparseness with (1.26±0.68) mm³ VOI. The ischemic (SUV_mean) gradually increased with time. Metabolism gradually recovered (F=121.82, 450.82, 435.75, P<0.05). The three doses of TFFC can eliminate free radicals and reduce the damage of myocardial injury. Amongst them, the high-dose group had a better effect on SOD, and the middle-dose group had a better effect on MDA and LDH. The low-dose group affected CK, and a significant difference was observed compared with the control group (P<0.05). After administration, the morphology of myocardial cells in each dose group was improved to some extent. Nuclear pyknosis, rupture, the apoptosis rate, etc. were significantly reduced, the number of cells increased. The high dose group showed the most obvious improvement.

Conclusions

The PET/CT imaging method can detect non-invasive, in vivo and dynamic MIRI, and can accurately evaluate the protective effect of traditional Mongolian medicine TFFC on MIRI. The Anti-MIRI of TFFC can scavenge free radicals, reduce oxidative stress damage, inhibit apoptosis, affect the activity of related enzymes.

Advances in heart rate variability signal analysis: joint position statement by the e-Cardiology ESC Working Group and the European Heart Rhythm Association co-endorsed by the Asia Pacific Heart Rhythm Society

Following the publication of the Task Force document on heart rate variability (HRV) in 1996, a number of articles have been published to describe new HRV methodologies and their application in different physiological and clinical studies. This document presents a critical review of the new methods. A particular attention has been paid to methodologies that have not been reported in the 1996 standardization document but have been more recently tested in sufficiently sized populations. The following methods were considered: Long-range correlation and fractal analysis; Short-term complexity; Entropy and regularity; and Nonlinear dynamical systems and chaotic behaviour. For each of these methods, technical aspects, clinical achievements, and suggestions for clinical application were reviewed. While the novel approaches have contributed in the technical understanding of the signal character of HRV, their success in developing new clinical tools, such as those for the identification of high-risk patients, has been rather limited. Available results obtained in selected populations of patients by specialized laboratories are nevertheless of interest but new prospective studies are needed. The investigation of new parameters, descriptive of the complex regulation mechanisms of heart rate, has to be encouraged because not all information in the HRV signal is captured by traditional methods. The new technologies thus could provide after proper validation, additional physiological, and clinical meaning. Multidisciplinary dialogue and specialized courses in the combination of clinical cardiology and complex signal processing methods seem warranted for further advances in studies of cardiac oscillations and in the understanding normal and abnormal cardiac control processes.

Ventricular Arrhythmias Among Implantable Cardioverter-Defibrillator Recipients for Primary Prevention

Background—

An implantable cardioverter-defibrillator (ICD) is the therapy of choice for primary prevention in patients with ischemia who are at risk for sudden cardiac death (SCD). One third of patients with significant coronary disease have chronic total coronary occlusion (CTO), which is associated with long-term mortality in patients with previous myocardial infarction. However, the impact of CTO on the occurrence of ventricular arrhythmias and long-term mortality in ICD recipients remains unknown.

Methods and Results—

All consecutive patients with coronary artery disease receiving ICD therapy for the prevention of SCD were included in the study. Among other characteristics, the existence of CTO was assessed. During follow-up, the occurrence of appropriate device delivery because of ventricular arrhythmias as well as mortality were noted. A total of 162 patients (mean age, 62±9 years; 93% men) with an ICD were included and followed for a median of 26 months (interquartile range, 12–42). At least 1 CTO was present in 71 (44%) patients. Appropriate device therapy was detected in 18% of the patients during the follow-up. The presence of CTO was associated with higher ventricular arrhythmia and mortality rates (log-rank test, <0.01). Multivariable analysis revealed that CTO was independently associated with appropriate ICD intervention (hazard ratio, 3.5; P =0.003).

Conclusions—

In patients with ischemic heart disease receiving ICDs for primary prevention of SCD, CTO is an independent predictor for the occurrence of ventricular arrhythmias and has an adverse impact on long-term mortality.

The importance of cardiac biomarkers on remodelling after myocardial infarction

Background

The purpose of this study is to evaluate the importance of tenascin-C ( TNC), N-terminal pro brain natriuretic peptide (NT-proBNP) and C-reactive protein (CRP) on LV remodelling after myocardial infarction (MI).

Methods

Fifty-seven stable patients with subacute anterior MI who had total or subtotal occlusion in the infarct-related left anterior desending artery in coronary angiography were enrolled the study. 18 of patients who had total occlusion received only medical theraphy, 19 of patients who had total occlusion received successful PCI+ medical theraphy and 20 of patients who had subtotal occlusion received successful PCI+ medical theraphy. Left ventricular volumes and ejection fractions (EF) were measured with echocardiography. Serum TNC, NT-proBNP and CRP levels were measured at admission and a month after treatment.

Results

There was significant increase in LV end-diastolic volume (LVEDV) and LV end-systolic volume (LVESV) baseline to follow-up in total-PCI group. Baseline to follow-up; a borderline significant increase was observed in LVEDV in the total-medical group. No significant difference was seen in LV volumes and EF in the subtotal-PCI group. NT-proBNP, TNC and CRP levels were decreased in all groups. The decrease in NT-proBNP and CRP values were significant in the total-medical and subtotal-PCI group but in the total-PCI group they were not significant. The decrease of TNC was significant in all groups but the lowest decrease was seen in the total-PCI group.

Conclusion

TNC, NT-proBNP and CRP reflect LV remodelling in accordance with echocardiography after MI.

Keywords

Tenascin-C; NT-pro BNP; CRP; Remodelling; Myocardial infarction

Short-Term Left Ventricular Remodeling After Revascularization in Subacute Total and Subtotal Occlusion With the Infarct-Related Left Anterior Descending Artery

Background

Large randomized studies revealed that percutaneous coronary intervention has no clinical benefit in patients with total occlusion. The purpose of this study is to evaluate left ventricular remodelling after PCI for total and subtotal infarct-related left anterior desending artery in stable patients who have not received trombolytic theraphy.

Methods

Sixty stable patients with subacute anterior myocardial infarction who have total or subtotal occlusion in the infarct-related left anterior descending artery were enrolled the study (20 patient in the total-medical group, 20 patient in the total-PCI group and 20 patient in the subtotal-PCI group). All patients’ left ventricular diameters, volumes and ejection fractions measured at admission and after a month.

Results

The necrotic segment number in scintigraphy were similar in three groups. In the total-PCI group, there were significant increases in left ventricular diastolic diameter, left ventricular end-diastolic volume and left ventricular end-systolic volume at first month. A borderline significant increase was observed in LVEDV in the total-medical group at first month. No significant difference was seen in all echocardiographic parameters in the subtotal-PCI group at a month after discharge. The percentage of increase in LVEDV was significantly higher and the percentage of increase in LVESV was borderline significantly higher in the total-PCI group than the other groups.

Conclusions

In stable patients, PCI for total occlusion in the subacute phase of anterior MI causes an increase in LV remodeling. Nevertheless PCI for subtotal occlusion in the subacute phase of anterior MI may prevent LV remodeling.

Left ventricular strain and strain rate echocardiography analysis in patients with total and subtotal occlusion in the infarct-related left anterior descending artery

BACKGROUND

Numerous studies show that percutaneous coronary intervention has no clinical benefit in patients with total occlusion. Both regional and global left ventricle (LV) functions may be evaluated in detail by strain (S) and strain rate (SR) echocardiography. The purpose of this study is to evaluate whether S and SR echocardiography may be used to determine the total occlusion.

METHOD

Sixty stable patients who have total or subtotal occlusion in the infarct-related left anterior descending artery were enrolled (Total occlusion group: 35 and subtotal occlusion group: 25 patients). In all patients, LV longitudinal S and SR data were obtained from total 14 segments.

RESULTS

S values of middle and apical segments of LV were significantly lower in the total occlusion groups. In SR analysis, middle and apical values of all walls were significantly different between the groups. The total SR of the middle and apical segments was significantly lower in the total occlusion group (respectively, total SR in middle segments: -3.4 ± 0.8% vs. -4.6 ± 1.0%, P < 0.00001 and total SR in apical segments: -1.7 ± 0.5% vs. -2.8 ± 0.6%, P = 0.001). The total SR values of four walls were also significantly lower in the total occlusion group (-10.3 ± 2.0% vs. -13 ± 3.1%, P < 0.0001). For predicting total occlusion, the highest sensitivity levels (84%) were obtained in SR of middle-anterior segment. SR of middle-septum and middle-lateral segments has the highest specificity levels (86%).

CONCLUSION

Total occlusion in stable patients with acute coronary syndrome has an unfavorable effect on the LV regional and global functions. Patients with total occlusion may be identified by S and SR echocardiography.