Early LAAO device migration after combined atrial fibrillation ablation and left atrial appendage occlusion.

The combined procedure of catheter ablation and percutaneous left atrial appendage occlusion for patients with atrial fibrillation has been shown to be safe and feasible using radiofrequency energy or cryoballoon.

Synergistic Coronary Artery Calcium Modification With Combined Atherectomy and Intravascular Lithotripsy.

BACKGROUND: Severe coronary artery calcification (CAC) remains challenging during percutaneous coronary intervention (PCI) and often requires 1 or more advanced calcium modification tools. OBJECTIVES: We describe the combination use of rotational (RA) or orbital atherectomy (OA), with intravascular lithotripsy (IVL), termed rotatripsy and orbital-tripsy, respectively, for modifying CAC prior to stent implantation during PCI. METHODS: We performed a retrospective analysis of patients treated with rotatripsy or orbital-tripsy at our center between July 2019 and March 2022. The primary efficacy endpoint was procedural success (successful stent implantation, <30% residual stenosis visually, Thrombolysis in Myocardial Infarction 3 flow; absence of types C to F dissection/perforation or loss of side branch ≥2.0mm visually) without in-hospital major adverse cardiovascular event (MACE, defined as cardiovascular death, myocardial infarction [MI], target-vessel revascularization). RESULTS: A total of 25 patients (14 rotatripsy and 11 orbital-tripsy) were included in our study. The mean age was 72.2 ± 7.6 years and 76% were men. PCI was guided by intravascular imaging in 24 patients (96%). All cases were treated with either RA or OA before utilization of IVL. Procedural success was achieved in 22 cases (88%) with 1 sidebranch loss without periprocedural MI (4%) and 2 in-patient deaths (8%) unrelated to the procedure (1 intracerebral hemorrhage and 1 cardiac arrest). CONCLUSION: We describe efficacious use of both rotatripsy and orbital-tripsy to modify severe CAC during PCI in a real-world setting. Intravascular imaging can guide appropriate use of these devices to complement each other to modify severe CAC to achieve optimal outcomes.

Thromboembolic events and hemorrhagic stroke after mRNA (BNT162b2) and inactivated (CoronaVac) covid-19 vaccination: A self-controlled case series study.

Background: This study aims to evaluate the association between thromboembolic events and hemorrhagic stroke following BNT162b2 and CoronaVac vaccination. Methods: Patients with incident thromboembolic events or hemorrhagic stroke within 28 days of covid-19 vaccination or SARS-CoV-2 positive test during 23 February to 30 September 2021 were included. The incidence per 100,000 covid-19 vaccine doses administered and SARS-CoV-2 test positive cases were estimated. A modified self-controlled case series (SCCS) analysis using the data from the Hong Kong territory-wide electronic health and vaccination records. Seasonal effect was adjusted by month. Findings: A total of 5,526,547 doses of BNT162b2 and 3,146,741 doses of CoronaVac were administered. A total of 334 and 402 thromboembolic events, and 57 and 49 hemorrhagic stroke cases occurred within 28 days after BNT162b2 and CoronaVac vaccination, respectively. The crude incidence of thromboembolic events and hemorrhagic stroke per 100,000 doses administered for both covid-19 vaccines were smaller than that per 100,000 SARS-CoV-2 test positive cases. The modified SCCS detected an increased risk of hemorrhagic stroke in BNT162b2 14-27 days after first dose with adjusted IRR of 2.53 (95% CI 1.48-4.34), and 0-13 days after second dose with adjusted IRR 2.69 (95% CI 1.54-4.69). No statistically significant risk was observed for thromboembolic events for both vaccines. Interpretation: We detected a possible safety signal for hemorrhagic stroke following BNT162b2 vaccination. The incidence of thromboembolic event or hemorrhagic stroke following vaccination is lower than that among SARS-CoV-2 test positive cases; therefore, vaccination against covid-19 remains an important public health intervention. Funding: This study was funded by a research grant from the Food and Health Bureau, The Government of the Hong Kong Special Administrative Region (reference COVID19F01).

Primary results from the Japanese Heart Failure and Sudden Cardiac Death Prevention Trial (HINODE).

AIMS: The HINODE study aimed to analyse rates of mortality, appropriately treated ventricular arrhythmias (VA), and heart failure in Japanese patients and compared with those in Western patients. METHODS AND RESULTS: After treatment decisions following contemporary practice in Japan, patients were prospectively enrolled into four cohorts: (i) internal cardioverter-defibrillator (ICD), (ii) cardiac resynchronization therapy (CRT) defibrillator (CRT-D), (iii) standard medical therapy ('non-device': ND), or (iv) pacing (indicated for CRT; received pacemaker or CRT pacing). Cohorts 1-3 required a left ventricular ejection fraction ≤35%, a history of heart failure, and a need for primary prevention of sudden cardiac death based on two to five previously identified risk factors. Endpoint outcomes were adjudicated by the independent committees. ICD and CRT-D cohorts, considered as high-voltage (HV) cohorts, were pooled for Kaplan-Meier analysis and propensity-matched to Multicenter Automatic Defibrillator Implantation Trial-Reduce Inappropriate Therapy (MADIT-RIT) arm B and C patients. The study enrolled 354 patients followed for 19.6 ± 6.5 months, with a minimum of 12 months. Propensity-matched HV cohorts showed comparable VA (P = 0.61) and mortality rates (P = 0.29) for HINODE and MADIT-RIT. The ND cohort presented a high crossover rate to ICD therapy (6.1%, n = 7/115), and the CRT-D cohort showed elevated mortality rates. The pacing cohort revealed that patients implanted with pacemakers had higher mortality (26.0%) than those with CRT-Pacing (8.4%, P = 0.05). CONCLUSIONS: The mortality and VA event rates of landmark trials are applicable to patients with primary prevention in Japan. Patients who did not receive guideline-indicated CRT devices had poor outcomes.

Behavior of AV synchrony pacing mode in a leadless pacemaker during variable AV conduction and arrhythmias.

INTRODUCTION: MARVEL 2 assessed the efficacy of mechanical atrial sensing by a ventricular leadless pacemaker, enabling a VDD pacing mode. The behavior of the enhanced MARVEL 2 algorithm during variable atrio-ventricular conduction (AVC) and/or arrhythmias has not been characterized and is the focus of this study. METHODS: Of the 75 patients enrolled in the MARVEL 2 study, 73 had a rhythm assessment and were included in the analysis. The enhanced MARVEL 2 algorithm included a mode-switching algorithm that automatically switches between VDD and ventricular only antibradycardia pacing (VVI)-40 depending upon AVC status. RESULTS: Forty-two patients (58%) had persistent third degree AV block (AVB), 18 (25%) had 1:1 AVC, 5 (7%) had variable AVC status, and 8 (11%) had atrial arrhythmias. Among the 42 patients with persistent third degree AVB, the median ventricular pacing (VP) percentage was 99.9% compared to 0.2% among those with 1:1 AVC. As AVC status changed, the algorithm switched to VDD when the ventricular rate dropped less than 40 bpm. During atrial fibrillation (AF) with ventricular response greater than 40 bpm, VVI-40 mode was maintained. No pauses longer than 1500 ms were observed. Frequent ventricular premature beats reduced the percentage of AV synchrony. During AF, the atrial signal was of low amplitude and there was infrequent sensing. CONCLUSION: The mode switching algorithm reduced VP in patients with 1:1 AVC and appropriately switched to VDD during AV block. No pacing safety issues were observed during arrhythmias.

Predictors of atrial mechanical sensing and atrioventricular synchrony with a leadless ventricular pacemaker: Results from the MARVEL 2 Study.

BACKGROUND: The MARVEL (Micra Atrial TRacking Using a Ventricular AccELerometer) 2 study assessed the efficacy of atrioventricular (AV) synchronous pacing with a Micra leadless pacemaker. Average atrioventricular synchrony (AVS) was 89.2%. Previously, low amplitude of the Micra-sensed atrial signal (A4) was observed to be a factor of low AVS. OBJECTIVE: The purpose of this study was to identify predictors of A4 amplitude and high AVS. METHODS: We analyzed 64 patients enrolled in MARVEL 2 who had visible P waves on electrocardiogram for assessing A4 amplitude and 40 patients with third-degree AV block for assessing AVS at rest. High AVS was defined as >90% correct atrial-triggered ventricular pacing. The association between clinical factors and echocardiographic parameters with A4 amplitude was investigated using a multivariable model with lasso variable selection. Variables associated with A4 amplitude together with premature ventricular contraction burden, sinus rate, and sinus rate variability (standard deviation of successive differences of P-P intervals [SDSD]) were assessed for association with AVS. RESULTS: In univariate analysis, low A4 amplitude was inversely related to atrial function assessed by E/A ratio and e'/a' ratio, and was directly related to atrial contraction excursion (ACE) and atrial strain (Ɛa) on echocardiography (all P ≤.05). The multivariable lasso regression model found coronary artery bypass graft history, E/A ratio, ACE, and Ɛa were associated with low A4 amplitude. E/A ratio and SDSD were multivariable predictors of high AVS, with >90% probability if E/A <0.94 and SDSD <5 bpm. CONCLUSION: Clinical parameters and echocardiographic markers of atrial function are associated with A4 signal amplitude. High AVS can be predicted by E/A ratio <0.94 and low sinus rate variability at rest.

Higher Incidence of Asymptomatic Cerebral Emboli After Atrial Fibrillation Ablation Found With High-Resolution Diffusion-Weighted Magnetic Resonance Imaging.

BACKGROUND: Asymptomatic cerebral emboli (ACE) are commonly seen on cerebral magnetic resonance imaging (MRI) after atrial fibrillation ablation, but the incidence in previous studies varies widely. No data exists to compare the effects of different diffusion-weighted imaging (DWI) settings on detecting ablation-related ACE. This self-control study sought to compare the incidence and characteristics of ablation-related ACE between high-resolution DWI and conventional DWI. METHODS: A total of 55 consecutive patients referred for atrial fibrillation ablation between December 2017 and September 2018 were enrolled. Patients underwent high-resolution DWI 1 day before ablation and repeated high-resolution DWI and conventional DWI within 48 hours post-ablation. The incidence, number, size, and location of ACE were compared between 2 DWI settings in the same patients. RESULTS: The high-resolution DWI revealed a higher incidence of acute ACE compared with conventional DWI (67.3% versus 41.8% of patients, P<0.001) and significantly more ACE (106 versus 45 lesions, P=0.001). For ACE seen on both scans, the size measured by high-resolution DWI was larger (5.42 versus 4.21 mm, P<0.001). No patients had any impaired neurocognitive performance during follow-up. Impaired left ventricular ejection fraction (P=0.012) and low intraoperative activated clotting time (P=0.009) level were associated with the occurrence of ACE in a multivariate analysis. CONCLUSIONS: High-resolution DWI revealed a higher incidence and greater details of post-ablation ACE in patients with atrial fibrillation. MRI settings significantly impact the detection of ACE and should be considered when comparing incidence rates of ACE among different studies. CLINICAL TRIAL REGISTRATION: URL: https://www.clinicaltrials.gov. Unique identifier: NCT01761188.

Atrioventricular Synchronous Pacing Using a Leadless Ventricular Pacemaker: Results From the MARVEL 2 Study.

OBJECTIVES: This study reports on the performance of a leadless ventricular pacemaker with automated, enhanced accelerometer-based algorithms that provide atrioventricular (AV) synchronous pacing. BACKGROUND: Despite many advantages, leadless pacemakers are currently only capable of single-chamber ventricular pacing. METHODS: The prospective MARVEL 2 (Micra Atrial tRacking using a Ventricular accELerometer 2) study assessed the performance of an automated, enhanced accelerometer-based algorithm downloaded to the Micra leadless pacemaker for up to 5 h in patients with AV block. The primary efficacy objective was to demonstrate the superiority of the algorithm to provide AV synchronous (VDD) pacing versus VVI-50 pacing in patients with sinus rhythm and complete AV block. The primary safety objective was to demonstrate that the algorithm did not result in pauses or heart rates of >100 beats/min. RESULTS: Overall, 75 patients from 12 centers were enrolled; an accelerometer-based algorithm was downloaded to their leadless pacemakers. Among the 40 patients with sinus rhythm and complete AV block included in the primary efficacy objective analysis, the proportion of patients with ≥70% AV synchrony at rest was significantly greater with VDD pacing than with VVI pacing (95% vs. 0%; p < 0.001). The mean percentage of AV synchrony increased from 26.8% (median: 26.9%) during VVI pacing to 89.2% (median: 94.3%) during VDD pacing. There were no pauses or episodes of oversensing-induced tachycardia reported during VDD pacing in all 75 patients. CONCLUSIONS: Accelerometer-based atrial sensing with an automated, enhanced algorithm significantly improved AV synchrony in patients with sinus rhythm and AV block who were implanted with a leadless ventricular pacemaker. (Micra Atrial Tracking Using a Ventricular Accelerometer 2 [MARVEL 2]; NCT03752151).

Clinical safety and performance of a MRI conditional pacing system in patients undergoing cardiac MRI.

BACKGROUND: Utilization of cardiac magnetic resonance imaging (cMRI) as an imaging modality in clinical practice is rapidly increasing. More evidence from randomized studies establishing clinical safety and performance of pacing systems in patients undergoing a cMRI scan is needed. OBJECTIVES: The purpose of this prospective, multicenter, randomized study was to demonstrate safety and efficacy of the Accent MRI™ conditional pacing systems (St. Jude Medical, St. Paul, MN, USA) in patients undergoing cMRI scan. METHODS: Patients (n  =  283) indicated for dual-chamber pacemaker implant were randomized to either the MRI Group (MG) (n  =  140) or the Control Group (CG) (n  =  143) after successful device implantation of the Accent MRI™ system. Clinical evaluation and device interrogation were performed at pre- and post-MRI scan, and 1 month post-MRI for all patients. At 9-12 weeks postimplant, patients in MG underwent a nondiagnostic cMRI scan at 1.5 Tesla (T), while patients in CG underwent device interrogation and clinical evaluation twice with a 45-minute waiting period in between. The safety endpoint was freedom from MRI scan-related complications and that for efficacy was significant changes in right atrial/ventricular capture threshold and sensing amplitude between right before MRI, immediately after MRI, and 1 month post-MRI. RESULTS: Results showed 100% freedom from MRI scan-related complications. There were no significant changes in device performance between pre-MRI scan and 1 month post-MRI scan time points in both study groups. CONCLUSIONS: cMRI scanning with 1.5 T scanners is safe in patients implanted with the Accent MRI™ conditional pacing system and has no significant effect on the electrical parameters of the device and leads.

Early pacing-induced systolic dyssynchrony is a strong predictor of left ventricular adverse remodeling: analysis from the Pacing to Avoid Cardiac Enlargement (PACE) trial.

BACKGROUND: Right ventricular apical (RVA) pacing is associated with adverse left ventricular (LV) remodeling and biventricular (BiV) pacing may prevent it although the mechanisms remain unclear. The current study aimed to assess the role of early pacing-induced systolic dyssynchrony (DYS) to predict adverse LV remodeling. METHODS: Patients with standard pacing indications and normal LV ejection fraction were randomized either to BiV (n=89) or RVA pacing (n=88). Pacing-induced DYS, defined as the standard deviation of the time to peak systolic velocity (Dyssynchrony Index) >33 ms in a 12-segmental model of LV, was measured by tissue Doppler echocardiography at 1 month. RESULTS: At 1 month, 59 patients (33%) had DYS which was more prevalent in RVA than BiV pacing group (52% vs. 15%, χ(2)=28.3, p<0.001), though Dyssynchrony Index was similar at baseline (30 ± 14 vs. 26 ± 11 ms, p=0.06). At 12 months, those developing DYS had significantly lower LV ejection fraction (55.1 ± 9.7 vs. 62.2 ± 7.9%, p<0.001) and larger LV end-systolic volume (35.3 ± 14.3 vs. 27.0 ± 10.4 ml, p<0.001) when compared to those without DYS. Reduction of ejection fraction ≥ 5% occurred in 67% (39 out of 58) of patients with DYS, but only in 18% (21 out of 115) in those without DYS (χ(2)=40.8, p<0.001). Both DYS at 1 month (odds ratio [OR]: 4.725, p=0.001) and RVA pacing (OR: 3.427, p=0.009) were independent predictors for reduction of ejection fraction at 12 months. CONCLUSION: Early pacing-induced DYS is a significant predictor of LV adverse remodeling and the observed benefit of BiV pacing may be related to the prevention of DYS. CLINICAL TRIAL REGISTRATION: Centre for Clinical Trials number, CUHK_CCT00037 (URL: http://www.cct.cuhk.edu.hk/Registry/publictrialrecord.aspx?trialid=CUHK_CCT00037).

Improved coronary artery blood flow following the correction of systolic dyssynchrony with cardiac resynchronization therapy.

BACKGROUND: Coronary blood flow (CBF) is improved by cardiac resynchronization therapy (CRT) and impaired by right ventricular apical (RVA) pacing in patients with heart failure. However, the underlying mechanism remains unclear. METHODS: Twenty-nine non-ischemic heart failure patients who responded to CRT underwent transthoracic echocardiography examination including both left anterior descending (LAD) CBF and tissue Doppler imaging in 3 pacing modes: intrinsic conduction, RVA pacing and biventricular (BiV) pacing. LAD velocity-temporal integral (LAD-VTI) and duration were measured. Systolic dyssynchrony was assessed with the standard deviation of a 12-left ventricular segmental model (Ts-SD). RESULTS: BiV pacing improved while RVA pacing reduced CBF compared to intrinsic conduction (all p<0.05). Both Ts-SD and ventricular septal velocity deteriorated during RVA pacing but improved during BiV pacing (all p<0.05). When systolic dyssynchrony was induced, lower LAD-VTI (9.5 ± 3.4 versus 12.7 ± 5.1cm, p=0.001) and shorter LAD diastolic duration (483 ± 92 versus 542 ± 106 ms, p=0.010) were detected than synchronous status. Systolic dyssynchrony was inversely related to septal velocity (r=-0.41), p<0.001 and LAD-VTI (r=-0.30, p=0.007), with the latter found to be moderately correlated to septal velocity (r=0.30, p=0.007). CONCLUSION: Regional LAD flow was improved in patients subjected to BiV but worsened in those treated with RVA pacing in non-ischemic heart failure CRT responders. Systolic dyssynchrony was more commonly observed in patients subjected to RVA pacing. Reduction of septal velocity with dyssynchrony may directly lead to reduced LAD flow. Improvement of septal velocity by CRT and hence LAD flow may be an important mechanism in determining the response to CRT.

Acute effects of right ventricular apical pacing on left atrial remodeling and function.

BACKGROUND: The acute effects of right ventricular apical (RVA) pacing on left atrial (LA) function in patients with normal ejection fraction are not clear. METHODS: A total of 94 patients (age 68.1 ± 11.1 years, 26 men) with implanted RVA-based dual-chamber pacemakers were recruited into this study. Patients who were pacemaker-dependent, in persistent atrial fibrillation or left ventricular ejection fraction <45% were excluded. Echocardiography (iE33, Philips, Andover, MA, USA) was performed during intrinsic ventricular conduction (V-sense) and RVA pacing (V-pace) with 15 minutes between switching modes. The total maximal LA volume (LAV(max)), preatrial contraction volume (LAV(pre)), and minimal volume (LAV(min)) were assessed by area-length method. Peak systolic, early diastolic, and peak late diastolic (atrial contractile) velocity (Sm-la, Em-la, and Am-la) and strain (ɛs-la, ɛe-la, and ɛa-la) were measured by color-coded tissue Doppler imaging (TDI) in four mid-LA walls at apical four- and two-chamber views. RESULTS: During V-pace, LA volumes increased significantly compared with V-sense (LAV(max): 52.0 ± 18.8 vs 55.2 ± 21.1 mL, P = 0.005; LAV(pre): 39.8 ± 16.4 vs 41.3 ± 16.6 mL, P = 0.014; LAV(min): 27.4 ± 14.0 vs 29.1 ± 15.1 mL, P = 0.001). TDI parameters showed significant reduction in Sm-la and Em-la. Furthermore, ɛs-la, ɛe-la, and ɛa-la decreased significantly, especially in patients with preexisting diastolic dysfunction (all P < 0.01). CONCLUSIONS: RVA pacing acutely induced LA enlargement and impaired atrial contractility. Patients with preexisting diastolic dysfunction may be more vulnerable to develop LA dysfunction and remodeling after acute RVA pacing.

Left atrial remodeling and reduced atrial pump function after chronic right ventricular apical pacing in patients with preserved ejection fraction.

BACKGROUND: This prospective study was to examine the impact of right ventricular apical (RVA) pacing on atrial remodeling and function. METHODS AND RESULTS: 103 patients (age 70 ± 11 years; 53 men) with preserved left ventricular (LV) ejection fraction (LVEF>45%) who received RVA pacing had Doppler echocardiography performed at baseline and after one year follow up. At one year follow up, left atrial (LA) volumes (pre-atrial contraction volume and the minimal volume) and their indexes were significantly increased with reduction in passive emptying fraction and total emptying fraction (all p<0.05). LA segmental tissue velocities - mean peak systolic (Sm-la), peak early diastolic (Em-la) and late diastolic (Am-la) - were also significantly reduced (all p<0.001). A reduction of Am-la>30% occurred in 24% of patients, and was more prevalent in patients with an elevation of LV filling pressure (E/e'>15) at one year (44.1% vs. 11.7%, χ(2)=12.75, p<0.001) as well as those with a reduction of LVEF ≥ 5% (34.0% vs. 14.3%, χ(2)=5.140, p=0.023). By multivariate regression analysis, E/e'>15 at one year (odds ratio [OR] 5.213; 95% confidence interval [CI] 1.778-15.281) and reduction of LVEF ≥ 5% (OR 3.181; 95% CI 1.045-9.686) were independent predictors of reduction of Am-la>30%. CONCLUSIONS: Chronic RVA pacing results in LA remodeling and reduced atrial function. This is related to elevated filling pressures and impairment of LV systolic function.

Biventricular pacing is superior to right ventricular pacing in bradycardia patients with preserved systolic function: 2-year results of the PACE trial.

AIMS: The Pacing to Avoid Cardiac Enlargement (PACE) trial is a prospective, double-blinded, randomized, multicentre study that reported the superiority of biventricular (BiV) pacing to right ventricular apical (RVA) pacing in the prevention of left ventricular (LV) adverse remodelling and deterioration of systolic function at 1 year. In the current analysis, we report the results at extended 2-year follow-up for changes in LV function and remodelling. METHODS AND RESULTS: Patients (n = 177) with bradycardia and preserved LV ejection fraction (EF ≥45%) were randomized to receive RVA or BiV pacing. The co-primary endpoints were LVEF and LV end-systolic volume (LVESV). Eighty-one (92%) of 88 in the RVA pacing group and 82 (92%) of 89 patients in the BiV pacing group completed 2-year follow-up with a valid echocardiography. In the RVA pacing group, LVEF further decreased from the first to the second year, but it remained unchanged in the BiV pacing group, leading to a significant difference of 9.9 percentage points between groups at 2-year follow-up (P < 0.001). Similarly, LVESV continues to enlarge from the first to the second year in the RVA pacing group, leading to a difference of 13.0 mL (P < 0.001) between groups. Predefined subgroup analysis showed consistent results with the whole study population for both co-primary endpoints, which included patients with pre-existing LV diastolic dysfunction. Eighteen patients in the BiV pacing group (20.2%) and 55 in the RVA pacing group (62.5%) had a significant reduction of LVEF (of ≥5%, P < 0.001). CONCLUSION: Left ventricular adverse remodelling and deterioration of systolic function continues at the second year after RVA pacing. This deterioration is prevented by BiV pacing.

The value of admission HbA(1c) level in diabetic patients with acute coronary syndrome.

BACKGROUND: Elevated admission glucose level is a strong predictor of short-term adverse outcome in patients with acute coronary syndrome (ACS). However, the prognostic value of diabetic control (ie, hemoglobin A(1c) levels) in patients with ACS is still undefined. HYPOTHESIS: Hemoglobin A(1c) level may predict short-term outcome in patients with ACS. METHODS: We conducted a retrospective study with prospective follow-up in 317 diabetic patients with ACS. Patients were stratified into 2 groups based on HbA(1c) level, checked within 8 weeks of the index admission (optimal control group, HbA(1c) ≤7%; suboptimal control group, HbA(1c) >7%). All patients were followed up prospectively for major adverse cardiovascular events (MACE) and mortality for 6 months. Short-term clinical outcomes were also compared between the 2 study groups. RESULTS: In our cohort, 27.4%, 46.4%, and 26.2% patients had unstable angina, non-ST-segment elevation myocardial infarction, and ST-segment elevation myocardial infarction, respectively. In-hospital mortality was similar in both HbA(1c) groups (3.37% vs 2.88%, P = 0.803). Six-month MACE was also similar (26.40% vs 26.47%, P = 0.919). All-cause mortality, cardiovascular mortality, symptom-driven revascularization, rehospitalization for angina, and hospitalization for heart failure were also similar in both groups. The hazard ratios for 6-month MACE and individual endpoints were also similar in both groups. CONCLUSIONS: This study suggests that HbA(1c) levels before admission are not associated with short-term cardiovascular outcome in diabetic patients subsequently admitted with ACS.

A novel multi-layer approach of measuring myocardial strain and torsion by 2D speckle tracking imaging in normal subjects and patients with heart diseases.

BACKGROUND: This study adopted a new multi-layer approach of measuring myocardial deformation by two-dimensional (2D) speckle tracking imaging to examine whether a transmural gradient exists in normal subjects and cardiac diseases. METHODS: Eighty patients were included with 20 in each group: (1) normal control; (2) acute coronary syndrome (ACS) with ejection fraction (EF) >45%; (3) right ventricular apical (RVA) pacing with EF>45%; (4) systolic heart failure (SHF) with EF<45%. Circumferential strain (ε-circum), torsion (Tor) and systolic dyssynchrony defined as the maximal difference in the time to peak circumferential strain were measured in the subendocardial and subepicardial myocardium layers (QLab 6.0, Philips). RESULTS: In all the 4 groups, a subendocardial to subepicardial gradient was present in both ε-circum (-20.7 ± 7.6 vs. -14.9 ± 5.6%, p<0.001) and Tor (12.0 ± 6.0 vs. 9.3 ± 4.7°, p<0.05), with higher values in the subendocardial layer. However, it was significantly narrowed for ε-circum (2.7 ± 1.2%) and Tor (0.8 ± 0.9°) in SHF patients (all p ≤ 0.001 vs. other groups). On the contrary, systolic dyssynchrony measured in the 2 layers showed no difference (264 ± 107 vs. 273 ± 110 ms, p = NS) and a homogenous distribution in ε-circum was observed from basal to apical planes (-17.0 ± 6.8 vs. -18.1 ± 7.4 vs. -18.1 ± 7.8%, all p = NS). CONCLUSIONS: A transmural gradient exists in circumferential strain and torsion, with higher values in the subendocardial layer. It might be reduced when systolic function is impaired. Therefore, the multi-layer approach of 2D speckle tracking imaging provides further information on assessment of myocardial diseases.

Different determinants of improvement of early and late systolic mitral regurgitation contributed after cardiac resynchronization therapy.

BACKGROUND: Functional mitral regurgitation (MR) at different phases of the regurgitant period may respond differently to cardiac resynchronization therapy (CRT). The aims of this study were to examine the impact of CRT on the phasic changes of MR (early vs late systole) and to explore the mechanisms of such changes. METHODS: Instantaneous MR flow rate and total MR volume were evaluated in 60 patients who had more than mild functional MR before and 3 months after CRT. In addition, indices of global left ventricular (LV) remodeling, mitral deformation, and LV systolic dyssynchrony were assessed. RESULTS: CRT diminished MR volume (38 ± 18 vs 32 ± 20 mL) by reducing both the early (72 ± 47 vs 58 ± 48 mL/sec) and late (48 ± 42 vs 40 ± 42 mL/sec) systolic components (all p values < .01). In patients with ≥10% reductions in total MR volume but not in patients without this improvement, there were significant reductions in LV end-systolic volume, increases in LV +dP/dt, decreases in mitral valvular tenting, and improvements of systolic dyssynchrony at 3 months (all P values < .05). By multivariate regression, the reductions in LV end-systolic volume and tenting area were independent determinants of a reduction in total MR volume: the reductions in LV end-systolic volume and global dyssynchrony determined the reduction in early systolic MR, and the reductions in tenting area and global dyssynchrony determined reduction in late systolic MR. CONCLUSIONS: CRT decreases MR volume by reducing both early and late systolic MR. The determinants of the phasic improvement in functional MR are different.

Impact of reduction in early- and late-systolic functional mitral regurgitation on reverse remodelling after cardiac resynchronization therapy.

AIMS: To examine whether the presence of pre-pacing functional mitral regurgitation (MR) and its improvement would affect the extent of left ventricular (LV) reverse remodelling after cardiac resynchronization therapy (CRT). METHODS AND RESULTS: Echocardiographic assessment was performed in 83 patients before and 3 months after CRT. Total MR volume and the early- and late-systolic MR flow rate were assessed. At 3 months, there was reduction in total MR volume (38 ± 20 vs. 33 ± 21 mL) with decrease in both early- (71 ± 52 vs. 60 ± 51 mL/s) and late-systolic (49 ± 46 vs. 42 ± 46 mL/s) MR flow rate (all P < 0.05). Receiver-operating characteristic curve found that an 11% decrease in total MR volume was associated with LV reverse remodelling [defined by the reduction in LV end-systolic volume (LVESV) of ≥15%] [sensitivity, 90%; specificity, 80%; area under the curve (AUC), 0.85; P < 0.001]. The improvement in early- and late-systolic MR was also associated with LV reverse remodelling, in which improvement in early-systolic MR had higher sensitivity, specificity, and AUC than late-systolic MR. The extent of reverse remodelling with gain in LV ejection fraction and forward stroke volume was greatest in patients with improvement in total MR, intermediate in those with mild or no MR at baseline, and the least in those without improvement in total MR (LVESV, -29.8 ± 12.0 vs. -18.6 ± 16.6 vs. -5.5 ± 8.6%; ejection fraction, 11.8 ± 6.2 vs. 7.0 ± 6.8 vs. 3.0 ± 5.0%; forward stroke volume, 43.1 ± 37.9 vs. 21.1 ± 26.1 vs. 6.8 ± 34.6%; all P < 0.05). CONCLUSION: Improvement of functional MR contributes to LV reverse remodelling after CRT, whereas reduction of early-systolic MR is more powerful than late-systolic MR.