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Cardiac auscultation by stethoscope is widely used but limited by low sensitivity and accuracy. Phonocardiogram was developed in an attempt to provide quantitative and qualitative information of heart sounds and murmurs by transforming acoustic signal into visual wavelet. Although phonocardiogram provides objective heart sound information and holds diagnostic potentials of different heart problems, its examination procedure is time-consuming and it requires specially trained technicians to operate the device. Acoustic cardiography (AUDICOR, Inovise Medical, Inc., Portland, OR, USA) is a major recent advance in the evolution of cardiac auscultation technology. The technique is more efficient and less operator-dependent. It synchronizes cardiac auscultation with ECG recording and provides a comprehensive assessment of both mechanical and electronic function of the heart. The application of acoustic cardiography is far beyond auscultation only. It generates various parameters which have been proven to correlate with gold standards in heart failure diagnosis and ischemic heart disease detection. Its application can be extended to other diseases, including LV hypertrophy, constrictive pericarditis, sleep apnea and ventricular fibrillation. The newly developed ambulatory acoustic cardiography is potentially used in heart failure follow-up in both home and hospital setting. This review comprehensively summarizes acoustic cardiographic research, including the most recent development., (Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.)

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., (© 2011 Wiley Periodicals, Inc.)

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., (Copyright © 2009 Elsevier Ireland Ltd. All rights reserved.)

LV electromechanical delay results in asynchronized contraction. However, it is not known if the presence of cardiac diseases without QRS prolongation may result in inter- or intraventricular asynchrony. This study investigated the occurrence of systolic mechanical delay in different regions of the LV in patients with underlying heart diseases and normal QRS duration. Tissue Doppler imaging (TDI) was performed in 141 patients (age 63.7 +/- 11.5 years) with underlying heart diseases (82% had ischemic heart disease) and 92 normal healthy volunteers (age 63.9 +/- 9.8 years) based on the four-basal and four-mid-segment model by apical views. Of these, 124 patients had normal QRS duration (< or = 120 ms) while 17 were prolonged due to LBBB or intraventricular conduction defect. Patients with normal QRS duration had significantly lower peak myocardial isovolumic contraction velocity (IVCM), sustained systolic velocity (SM), and prolonged time to peak IVCM and SM in almost all myocardial segments when compared to controls. The time to peak IVCM (basal lateral vs basal septal segment: 61.0 +/- 29.4 vs 53.3 +/- 24.1 ms, P < 0.005) and SM (basal lateral vs basal septal segment: 174 +/- 44 vs 154 +/- 36 ms, P < 0.001) was further delayed in the LV free-wall segments. Mechanical delay was also evident in the LV free-wall segments in patients with preserved or impaired systolic function, in patients with or without previous myocardial infarction, and in patients with prolonged QRS duration. Patients with prolonged QRS had a higher prevalence of LV free-wall delay of > 50 ms (47 vs 24%, chi-square = 4.6, P < 0.05). In conclusion, the presence of cardiac diseases was characterized by LV global mechanical delay; and, intraventricular asynchronized contraction characterized mostly by further mechanical delay in the free-wall region. These changes occur even in those with normal QRS duration.

Objectives: Patients with very severe aortic stenosis (AS) have extremely poor clinical outcomes even if they are asymptomatic compared to those with severe AS, but the clinical and echocardiographic characteristics of patients with very severe AS remain unclear. Methods: The Asian Valve Registry is a prospective, multicenter, multinational registry for the study and identification of the incidence, natural course, clinical outcomes, and prognostic factors for patients with significant AS at 9 centers in Asian countries. Severe AS was observed in 367 of 1066 patients with AS, and 212 were classified as very severe AS, defined as a peak aortic valve velocity ≥5.0 m/s or a mean aortic valve gradient ≥60 mm Hg. Results: The prevalence of NYHA functional class II–IV among patients with very severe AS was significantly higher than that among patients with severe AS (67.9% vs 51.5%, P < .001). As for echocardiographic parameters, it was noteworthy that left ventricular mass index (LVMI) and left atrial volume index (LAVI) for patients with very severe AS were significantly larger than those for patients with severe AS (LVMI: 145.1 ± 36.4 g/m2 vs 119.2 ± 32.1 g/m2, P < .0001; LAVI: 56.1 ± 24.6 mL/m2 vs 49.8 ± 22.6 mL/m2, P = .002). Moreover, multivariate logistic regression analysis showed that LVMI was the only independently associated with NYHA functional class II–IV in patients with very severe AS. Conclusions: Our findings may well have clinical implications for better management of patients with AS and lead to better understanding of poor outcomes for patients with very severe AS. [ABSTRACT FROM AUTHOR]

Aims We report the results of long-term follow-up of the Pacing to Avoid Cardiac Enlargement ( PACE) trial, a prospective, double-blinded, randomized, multicentre study that confirmed the superiority of biventricular ( BiV) pacing compared with right ventricular apical ( RVA) pacing in prevention of LV adverse remodelling and deterioration of systolic function at 1 and 2 years. Methods and results Patients with bradycardia and preserved LVEF were randomized to receive RVA ( n = 88) or BiV pacing ( n = 89). Co-primary endpoints were LV end-systolic volume ( LVESV) and LVEF measured by echocardiography. There were 149 patients who had extended follow-up, with a mean duration of 4.8 ± 1.5 years (2.5-7.8 years). The primary endpoint analyses were performed in 146 patients (74 in the RVA group and 72 in the BiV group). In the RVA pacing group, the LVEF decreased while the LVESV increased progressively at follow-up, but remained unchanged in the BiV pacing group. The differences in LVEF between the RVA and BiV groups were -6.3, -9.2, and -10.7% at 1-year, 2-year, and long-term follow-up, respectively (all P < 0.001). The corresponding differences in LVESV were +7.4, +9.9, and +13.1 mL, respectively (all P < 0.001). The deleterious effects of RVA pacing consistently occurred in all the pre-defined subgroups. Furthermore, patients with RVA pacing had a significantly higher prevalence of heart failure hospitalization than the BiV group (23.9% vs. 14.6%, log-rank χ2 = 7.55, P = 0.006). Conclusion Left ventricular adverse remodelling and deterioration of systolic function continued at long-term follow-up in patients with RVA pacing; this deterioration was prevented by the use of BiV pacing. Also, heart failure hospitalization was more prevalent in the RVA pacing group. Trial registration CUHK_CCT00037. [ABSTRACT FROM AUTHOR]

Aims Rho kinases (ROCKs) are the best characterized effectors of the small G-protein RhoA, and play a role in enhanced vasoconstriction in animal models of congestive heart failure (CHF). This study examined if ROCK activity is increased in CHF and how it is associated with the outcome in CHF. Methods and results Patients admitted with CHF (n =178), disease controls (n =31), and normal subjects (n =30) were studied. Baseline ROCK activity was measured by phosphorylation of themyosin-binding subunit in peripheral leucocytes. The patients were followed up for 14.4 ± 7.2 months (range 0.5–26 months) or until the occurrence of cardiac death. The ROCK activity in CHF patients (2.93 ± 0.87) was significantly higher than that of the disease control (2.06 ± 0.38, P < 0.001) and normal control (1.57 ± 0.43, P < 0.001) groups. Similarly, protein levels of ROCK1 and ROCK2 as well as the activity of RhoA in CHF were significantly higher than in disease controls and normal controls (all P < 0.05). Dyspnoea at rest (β =0.338, P < 0.001), low left ventricular ejection fraction (β = –0.277, P < 0.001), and high creatinine (β =0.202, P =0.006) were independent predictors of the baseline ROCK activity in CHF. Forty-five patients died within 2 years follow-up (25.3%). Combining ROCK activity and N-terminal pro brain natriuretic peptide (NT-proBNP) had an incremental value (log rank χ2 =11.62) in predicting long-term mortality when compared with only NT-proBNP (log rank χ2 =5.16, P < 0.05). Conclusion ROCK activity is increased in CHF and it might be associated with the mortality in CHF. ROCK activity might be a complementary biomarker to CHF risk stratification. [ABSTRACT FROM AUTHOR]

Aims: Left atrial (LA) size is considered a marker of poor prognosis in heart failure (HF) patients. Prior studies have recruited relatively few subjects limiting their power to adequately analyse the interaction between LA size, left ventricular (LV) systolic and diastolic function, and prognosis. [ABSTRACT FROM PUBLISHER]

Tissue Doppler imaging (TDI) is evolving as a useful echocardiographic tool for quantitative assessment of left ventricular (LV) systolic and diastolic function. Recent studies have explored the prognostic role of TDI-derived parameters in major cardiac diseases, such as heart failure, acute myocardial infarction, and hypertension. In these conditions, myocardial mitral annular or basal segmental (Sm) systolic and early diastolic (Ea or Em) velocities have been shown to predict mortality or cardiovascular events. In particular, those with reduced Sm or Em values of <3 cm/s have a very poor prognosis. In heart failure and after myocardial infarction, noninvasive assessment of LV diastolic pressure by transmitral to mitral annular early diastolic velocity ratio (E/Ea or E/Em) is a strong prognosticator, especially when E/Ea is ≥15. In addition, systolic intraventricular dyssynchrony measured by segmental analysis of myocardial velocities is another independent predictor of adverse clinical outcome in heart failure subjects, even when the QRS duration is normal. In heart failure patients who received cardiac resynchronization therapy, the presence of systolic dyssynchrony at baseline is associated with favorable LV remodeling, which in turn predicts a favorable long-term clinical outcome. Finally, TDI and derived deformation parameters improve prognostic assessment during dobutamine stress echocardiography. A high mean Sm value in the basal segments of patients with suspected coronary artery disease is associated with lower mortality rate or myocardial infarction and is superior to the wall motion score. [Copyright &y& Elsevier]

Introduction: Cardiac resynchronization therapy (CRT) is now an established nonpharmacologic therapy for advanced heart failure with electromechanical delay. Despite compelling evidence of the benefits of CRT, one troubling issue is the lack of a favorable response in about one-third of patients. Methods and Results: Currently, there is no unifying definition of responders, and published data were based on acute hemodynamic changes, chronic left ventricular reverse remodeling, as well as the intermediate or long-term clinical response. The lack of improvement with CRT can be due to many factors including the placement of the left ventricular pacing lead in an inappropriate location, the absence of electrical conduction delay or mechanical dyssynchrony despite wide QRS complexes, and possibly failure to optimize the CRT settings after device implantation. In acute hemodynamic studies, placing the left ventricular leads at the free wall region has been suggested to generate the best pulse pressure and positive dp/dt. The degree of mechanical dyssynchrony has recently been assessed noninvasively in CRT patients by echocardiography and in particular by tissue Doppler imaging. These studies suggested that responders of left ventricular reverse remodeling or systolic function had more severe systolic dyssynchrony. However, further studies are needed to examine the clinical utility of these parameters when applied to the standardized anatomic or functional endpoints. Optimization of atrioventricular and interventricular pacing intervals may also reduce the number of nonresponders, though newer methods, especially interventricular pacing intervals, are still under clinical investigation. Conclusion: With the adjunctive use of imaging technology, physicians are able to characterize the response to CRT objectively, and cardiac imaging is an important clinical tool for determining more precisely the presence and degree of mechanical dyssynchrony. [ABSTRACT FROM AUTHOR]

Although the beneficial role of cardiac resynchronization therapy (CRT) in selected patients with heart failure is well proven, its effect on the incidence of atrial fibrillation (AF) is unclear. The present study compared the incidence of AF in 36 consecutive patients with chronic heart failure receiving CRT with its incidence in controls matched for age, gender, and left ventricular ejection fraction but not receiving CRT. The findings suggest that patients with CRT had a significantly lower incidence of AF than controls. Further studies to establish the role of CRT in preventing AF and its mechanisms are warranted. [Copyright &y& Elsevier]

Background: The aim of the study was to assess the degree of left ventricular (LV) asynchrony after myocardial infarction (MI) in patients with a narrow QRS complex using tissue Doppler imaging (TDI) and correlate this with the site and extent of the infarction measured by contrast-enhanced magnetic resonance imaging (Ce-MRI). Methods: Echocardiography with TDI and Ce-MRI was performed within 6 days of acute MI in 47 patients and compared with 69 age-matched healthy volunteers. Regional myocardial velocities were assessed in 12 segments, and the corresponding systolic velocity (Sm), early diastolic velocity (Em), as well as the time to peak Sm (Ts) and time to peak Em (Te) were measured. To assess LV synchronicity, SDs of Ts (Ts-SD) and Te (Te-SD) of all 12 segments were computed. Location and size of infarct were confirmed by Ce-MRI with a 16-segment model. Results: All the patients had a normal QRS complex duration. The Ts-SD was significantly prolonged in the MI group when compared with controls (42.2 ± 13.7 vs 18.0 ± 7.0 milliseconds, P < .001). The Ts-SD was longer in patients with anterior than inferior MI (46.8 ± 13.9 vs 34.6 ± 8.5 milliseconds, P = .002). Stepwise multiple regression analysis revealed that infarct size was the main independent predictor of systolic asynchrony (B = 0.79, 95% CI 0.75-1.23, P < .001). Asynchrony was not related to the transmurality of the infarction. Conclusions: Myocardial infarction has a significant impact on LV synchronicity even in those with a narrow QRS complex. The degree of LV systolic asynchrony is mainly determined by the infarct size and not transmurality. [Copyright &y& Elsevier]

This study evaluated the performance of a new lead for permanent left ventricular (LV) pacing via the coronary sinus (CS) in four men and nine women (mean age = 71 ± 13 years) with sick sinus syndrome. It consists of a 75-cm-long, 4.8-Fr, unipolar ventricular lead with a distal portion preshaped in an S curve to provide steerability and stability within the CS. Its efficacy and stability for permanent LV pacing were tested at implant, predischarge, and at 1, 3 and 6 months of follow-up. The lead was successfully implanted in 11 ⁄13 patients (65%) within a mean fluoroscopy time of 35 ± 22 minutes. The final positions of the electrodes at the tip of the lead within venous tributaries of the CS were: (1) anterior (n = 2, 18%); (2) posterolateral (n = 5, 45%); and (3) the lateral (n = 4, 36%). Unsuccessful implants were due to unstable lead position (n = 1), or high pacing threshold (n = 1). There was no postprocedural lead dislodgment or significant changes in the R wave amplitude, LV pacing threshold and lead impedance up to 6 months of follow-up. In summary, this initial experience suggests that this new lead offers safe and reliable permanent LV pacing via the CS in the majority of patients and may be used in isolation or in conjunction with right ventricular pacing for biventricular synchronization. [ABSTRACT FROM AUTHOR]

The authors discuss the difficult areas for cardiac resynchronization therapy, optimization of the treatment for implanting the left ventricular (LV) lead and the factors that affected the efficacy of LV. They mention about the study by Kristiansen and colleagues that described the role of employing 2-dimensional speckle tracking technology in assessing LV segmental function in heart failure patients. They state the methods to measure the anteroposterior wall delay in LV mid-cavity level.

Left ventricular lead dislodgement remained a problem for cardiac resynchronization therapy and is one of the major causes of repeated procedures. We report a 30-year-old lady with possible left ventricular lead dislodgement related to hyperpnea respiration. [ABSTRACT FROM AUTHOR]

Left ventricular (LV) systolic dyssynchrony is an important pathologic mechanism in patients with heart failure (HF). However, the prevalence of intraventricular dyssynchrony in patients with different LV ejection fractions (EFs) is unknown. This study evaluated 402 consecutive patients with HF (mean age 64.99 ± 13.15 years, 72.4% men) and 120 healthy controls. Dyssynchrony indexes included the SD of the time to peak systolic velocity (Ts) in ejection phase in the 12-segmental model (Ts-SD) and the difference in Ts between basal septal and basal lateral segments (Ts-Septal-Lateral) using tissue Doppler imaging. Patients were divided into 3 groups according to LVEF (LVEF <20%, >20% to 35%, and >35% to 50%) and compared with healthy controls. Both indexes were significantly higher in all 3 LVEF groups compared with controls (p <0.0001). Based on the established cut-off values, systolic dyssynchrony was equally prevalent in all 3 LVEF groups and was 67%, 62%, and 55% using Ts-SD and 38%, 36%, and 35% using Ts-Septal-Lateral, respectively. However, the prevalence of systolic dyssynchrony was higher using Ts-SD than Ts-Septal-Lateral (chi-square = 94.43, p <0.001). Conversely, the prevalence of electrical dyssynchrony, defined as a >120-ms QRS duration, decreased significantly with increasing LVEF (44%, 35%, and 16%; chi-square 5.60, p <0.001). In conclusion, the prevalence of mechanical systolic dyssynchrony was independent of severity of LV systolic dysfunction. This may implicate the potential role of cardiac resynchronization therapy for those with LVEF of 35% to 50%, in particular when systolic dyssynchrony is present. [Copyright &y& Elsevier]

Abstract: Background and objective: Doppler echocardiographic assessment of diastolic filling provides a non-invasive estimate of left ventricular (LV) filling pressure and the most advanced diastolic filling grade, the restrictive filling pattern (RFP), has been linked to prognosis in patients post acute myocardial infarction (AMI) and with heart failure (HF). There remains some uncertainty about the prognostic role of RFP in patients with varied levels of systolic function. The objective of this collaboration is to determine whether the presence of RFP offers additional prognostic information over LV systolic function, symptoms or other clinical factors in patients post AMI or with HF. Methods: The Meta-analysis Research Group in Echocardiography (MeRGE) has been established in order to test this through two individual patient meta-analyses. Prospective studies that enrolled patients with either established HF or post AMI and included Doppler-echocardiography and outcome data will be merged into two large datasets (3739 AMI patients and 3540 HF patients) in order to evaluate the independent effects of RFP upon total and cardiovascular mortality using Kaplan–Meier survival analysis methods and Cox proportional Hazards model for multi-variate analysis. Survival will be examined within different bands of LV systolic function based upon ejection fraction (EF). Implications: This unique dataset will provide a very large cohort of patients, which will be adequately powered to provide new and prognostically important information to further aid risk stratification in these two high-risk patient groups. [Copyright &y& Elsevier]