Mitral annular systolic velocity reflects the left atrial appendage function in mitral stenosis

BACKGROUND: Left atrial appendage (LAA) dysfunction is an independent predictor of thromboembolism in mitral stenosis (MS). OBJECTIVES: To investigate whether there is a relation between annular velocities obtained by tissue Doppler imaging and LAA function and to determine if the annular velocities can predict the presence of the inactive LAA in MS. METHODS: Eighty-five MS patients and 80 healthy controls were evaluated by transthoracic echocardiography and all patients underwent transesophageal echocardiography. The annular systolic (S-wave) and diastolic (E- and A-waves) velocities were recorded. Inactive LAA was defined as LAA emptying velocity <25 cm/sec. Patients were divided into three groups; group I (n = 43): sinus rhythm (SR) and LAA emptying velocity > or =25 cm/sec, group II (n = 15): SR and LAA emptying velocity <25 cm/sec and group III (n = 27): atrial fibrillation. RESULTS: Thrombus was detected in 12 patients and spontaneous echo contrast (SEC) was detected in 48 patients. Both S-wave and peak LAA emptying velocities were decreasing, while SEC frequency and density were increasing from group I to group III. There was a positive correlation between LAA emptying and S-wave velocities (P < 0.001, r = 0.682). Multivariate regression analysis showed that only S-wave is the independent predictor of inactive LAA (P = 0.001, odds ratio = 0.143, 95% CI = 0.047-0.434). In patients with SR, the cutoff value of S-wave was 13.5 cm/sec for the prediction of the presence of inactive LAA (sensitivity: 95.3%, specificity: 93.3%). CONCLUSIONS: S-wave is an independent predictor of inactive LAA and a useful parameter in estimating inactive LAA in MS with SR.     

Changes in Left Atrial Appendage Dimensions Following Volume Loading During Percutaneous Left Atrial Appendage Closure

ObjectivesThis study sought to determine whether volume loading alters the left atrial appendage (LAA) dimensions in patients undergoing percutaneous LAA closure.BackgroundPercutaneous LAA closure is increasingly performed in patients with atrial fibrillation and contraindications to anticoagulation, to lower their stroke and systemic embolism risk. The safety and efficacy of LAA closure relies on accurate device sizing, which necessitates accurate measurement of LAA dimensions. LAA size may change with volume status, and because patients are fasting for these procedures, intraprocedural measurements may not be representative of true LAA size.MethodsThirty-one consecutive patients undergoing percutaneous LAA closure who received volume loading during the procedure were included in this study. After an overnight fast and induction of general anesthesia, patients had their LAA dimensions (orifice and depth) measured by transesophageal echocardiography before and after 500 to 1,000 ml of intravenous normal saline, aiming for a left atrial pressure >12 mm Hg.ResultsSuccessful implantation of LAA closure device was achieved in all patients. The average orifice size of the LAA at baseline was 20.5 mm at 90°, and 22.5 mm at 135°. Following volume loading, the average orifice size of the LAA increased to 22.5 mm at 90°, and 23.5 mm at 135°. The average increase in orifice was 1.9 mm (p < 0.0001). The depth of the LAA also increased by an average of 2.5 mm after volume loading (p < 0.0001).ConclusionsIntraprocedural volume loading with saline increased the LAA orifice and depth dimensions during LAA closure. Operators should consider optimizing the left atrial pressure with volume loading before final device sizing.     

Percutaneous Left Atrial Appendage Closure With the Watchman Device: Long-Term Results Up to 5 Years

ObjectivesThe aim of this study was to evaluate long-term outcomes in patients with atrial fibrillation undergoing percutaneous left atrial appendage (LAA) closure with the Watchman device.BackgroundAtrial fibrillation is one of the most common arrhythmias and is associated with a high risk for cardioembolic ischemic events, most notably stroke. Percutaneous LAA closure is an alternative to oral anticoagulation, because most thrombi originate from the LAA.MethodsAll consecutive patients with minimum CHADS₂ or CHA₂DS₂-VASc scores of 1 who underwent LAA closure with the Watchman device between June 2006 and August 2010 were eligible. Follow-up examinations were performed after 45 days to 3 months, 6 months, and 1 year and thereafter annually. Afterward, alternating office visits and telephone follow-up were performed every 6 months.ResultsA total of 102 patients were included. The mean age was 71.6 ± 8.8 years, and 37.3% were women. The mean CHADS₂ and CHA₂DS₂-VASc scores were 2.7 ± 1.3 and 4.3 ± 1.7, respectively. Procedural success was achieved in 96.1% of patients. During a mean follow-up period of 3.0 ± 1.6 years, the annual rates of transient ischemic attack, stroke, intracranial hemorrhage, and death were 0.7%, 0.7%, 1.1%, and 3.5%, respectively.ConclusionsLAA closure with the Watchman device is safe and feasible for stroke protection in patients with atrial fibrillation. Low ischemic events rates demonstrate its effectiveness during long-term follow-up.     

Left ventricular diastolic dysfunction in patients with COPD in the presence and absence of elevated pulmonary arterial pressure

BACKGROUND: Increased right ventricular afterload leads to left ventricular diastolic dysfunction due to ventricular interdependence. Increased right ventricular afterload is frequently present in patients with COPD. The purpose of this study was to determine whether left ventricular diastolic dysfunction could be detected in COPD patients with normal or elevated pulmonary artery pressure (PAP). METHODS: Twenty-two patients with COPD and 22 matched control subjects underwent pulsed Doppler echocardiography. Left ventricular systolic dysfunction and other causes of left ventricular diastolic dysfunction (eg, coronary artery disease) were excluded in all patients and control subjects. PAP was measured invasively in 13 patients with COPD. RESULTS: The maximal atrial filling velocity was increased and the early filling velocity was decreased in patients with COPD compared to control subjects. The early flow velocity peak/late flow velocity peak (E/A) ratio was markedly decreased in patients with COPD compared to control subjects (0.79 +/- 0.035 vs 1.38 +/- 0.069, respectively; p < 0.0001), indicating the presence of left ventricular diastolic dysfunction. The atrial contribution to total left diastolic filling was increased in patients with COPD. This was also observed in COPD patients with normal PAP, as ascertained using a right heart catheter. The atrial contribution to total left diastolic filling was further increased in COPD patients with PAP. PAP correlated with the E/A ratio (r = -0.85; p < 0.0001). CONCLUSIONS: Left ventricular diastolic dysfunction is present in COPD patients with normal PAP and increases with right ventricular afterload.     

The Left Atrial Appendage: Anatomy,Function, and Noninvasive Evaluation

The left atrial appendage (LAA) is a finger-like extension originating from the main body of the left atrium. Atrial fibrillation (AF) is the most common clinically important cardiac arrhythmia, occurring in approximately 0.4% to 1% of the general population and increasing with age to >8% in those >80 years of age. In the presence of AF thrombus, formation often occurs within the LAA because of reduced contractility and stasis; thus, attention should be given to the LAA when evaluating and assessing patients with AF to determine the risk for cardioembolic complications. It is clinically important to understand LAA anatomy and function. It is also critical to choose the optimal imaging techniques to identify or exclude LAA thrombi in the setting of AF, before cardioversion, and with current and emerging transcatheter therapies, which include mitral balloon valvuloplasty, pulmonary vein isolation, MitraClip (Abbott Laboratories, Abbott Park, Illinois) valve repair, and the implantation of LAA occlusion and exclusion devices. In this review, we present the current data regarding LAA anatomy, LAA function, and LAA imaging using the currently available noninvasive imaging modalities.     

Left ventricular diastolic performance at rest is essential for exercise capacity in patients with non-complicated myocardial infarction

IntroductionIn patients with recent myocardial infarction (MI) limited exercise capacity during physical activity is an important symptom and the base for future treatment. The myocardial injury after MI leads to both systolic and diastolic left ventricular (LV) dysfunction.ObjectiveThe aim of this study was to assess the relevance of systolic and diastolic LV function for cardiopulmonary exercise capacity in patients with prior MI.MethodsSixty-five consecutive patients after first MI without signs and symptoms of heart failure, aged 52 ± 6 years, were included in the study. The following echo parameters were evaluated: LV ejection fraction (LVEF), peak early and late diastolic velocities (E, A), deceleration time of E wave (dec t E), ratio of early trans-mitral to early annular diastolic velocities (E/e′), velocity propagation of early filling (Vp), and diameters and volumes of LV and left atrium (LA). CPET variables included: oxygen uptake at peak exercise (peak VO₂), oxygen pulse (VO₂ HR), VE/VCO₂ slope, circulatory power (CP) and recovery half time (T1/2).ResultsSignificant correlations were demonstrated between peak VO₂ and E/e’ (p < 0.001), peak VO₂ and dec t E (p < 0.001), VO₂ HR and E/e′ (p = 0.002) and between VE/VCO₂ and E/e′ (p < 0.001). Twenty patients with elevated LV filling pressure achieved significantly lower peak VO₂ (1624 vs. 1932 ml, p = 0.027) VO₂ HR (11.70 vs. 14.05, p = 0.011) and CP (287,073 vs. 361,719, p = 0.014). By using multivariate regression model we found that only E/e′ (p = 0.001) and dec t E (p = 0.008) significantly contributed to peak VO₂.ConclusionsDiastolic dysfunction, particularly LV filling pressure, determine exercise capacity, despite differences in LV ejection fraction in patients with prior MI.     

Percutaneous Left Atrial Appendage Closure: Procedural Techniques and Outcomes

Percutaneous left atrial appendage closure technology for stroke prevention in patients with atrial fibrillation has significantly advanced in the past 2 decades. Several devices are under clinical investigation, and a few have already received Conformité Européene (CE)-mark approval and are available in many countries. The WATCHMAN device (Boston Scientific, Natick, Massachusetts) has the most supportive data and is under evaluation by the U.S. Food and Drug Administration for warfarin-eligible patients. The Amplatzer Cardiac Plug (St. Jude Medical, Plymouth, Minnesota) has a large real-world experience over the past 5 years, and a randomized trial comparing Amplatzer Cardiac Plug with the WATCHMAN device is anticipated in the near future. The Lariat procedure (SentreHEART Inc., Redwood City, California) has also gained interest lately, but early studies were concerning for high rates of serious pericardial effusion and major bleeding. The current real-world experience predominantly involves patients who are not long-term anticoagulation candidates or who are perceived to have high bleeding risks. This pattern of practice is expected to change when the U.S. Food and Drug Administration approves the WATCHMAN device for warfarin-eligible patients. This paper reviews in depth the procedural techniques, safety, and outcomes of the current leading devices.     

Periprocedural Intracardiac Echocardiography for Left Atrial Appendage Closure: A Dual-Center Experience

ObjectivesThis dual-center study sought to demonstrate the utility and safety of intracardiac echocardiography (ICE) in providing adequate imaging guidance as an alternative to transesophageal echocardiography (TEE) during Amplatzer Cardiac Plug device implantation.BackgroundOver 90% of intracardiac thrombi in atrial fibrillation originate from the left atrial appendage (LAA). Patients with contraindications to anticoagulation are potential candidates for LAA percutaneous occlusion. TEE is typically used to guide implantation.MethodsICE-guided percutaneous LAA closure was performed in 121 patients to evaluate the following tasks typically achieved by TEE: assessment of the LAA dimension for device sizing; guidance of transseptal puncture; verification of the delivery sheath position; confirmation of location and stability of the device before and after release and continuous monitoring to detect procedural complications. In 51 consecutive patients, we compared the measurements obtained by ICE and fluoroscopy to choose the size of the device.ResultsThe device was successfully implanted in 117 patients, yielding a technical success rate of 96.7%. Procedural success was achieved in 113 cases (93.4%). Four major adverse events (3 cardiac tamponades and 1 in-hospital transient ischemic attack) occurred. There was significant correlation in the measurements for device sizing assessed by angiography and ICE (r = 0.94, p < 0.0001).ConclusionsICE imaging was able to perform the tasks typically provided by TEE during implantation of the Amplatzer Cardiac Plug device for LAA occlusion. Therefore, we provide evidence that the use of ICE offered accurate measurements of LAA dimension in order to select the correct device sizes.     

Clinical application of tissue Doppler imaging in patients with idiopathic pulmonary hypertension

BACKGROUND: Tissue Doppler (TD) echocardiographic imaging of mitral and tricuspid annulus has been applied to assess right ventricular (RV) and left ventricular (LV) function in many cardiac diseases, but its clinical application, including response to long-term targeted therapy in patients with idiopathic pulmonary hypertension (PH), has not been addressed. METHODS: Seventy patients with idiopathic PH were compared with 35 age-matched control subjects to examine myocardial velocities by TD. Of these, 35 patients underwent repeat imaging after long-term targeted therapy. In addition, 50 consecutive patients with idiopathic PH with simultaneous right-heart catheterization and echocardiography were examined. RESULTS: No significant differences were noted between PH patients and the control group in lateral mitral annulus systolic velocity and early diastolic velocity (Ea) by TD, but septal velocities were significantly lower (p < 0.01). With targeted therapy, myocardial velocities at the septum and RV free wall increased significantly (p < 0.05). Likewise, E/Ea ratio increased, albeit still in the normal range. In all 50 patients with invasive measurements, lateral E/Ea ratio readily identified normal mean pulmonary capillary wedge pressure (PCWP). CONCLUSIONS: TD imaging of the lateral mitral annulus can reliably predict the presence of normal/reduced mean PCWP in patients with idiopathic PH, and track the improvement in RV function and LV filling with long-term targeted therapy.     

Bleeding Outcomes After Left Atrial Appendage Closure Compared With Long-Term Warfarin: A Pooled,Patient-Level Analysis of the WATCHMAN Randomized Trial Experience

ObjectivesThe purpose of this study was to compare the relative risk of major bleeding with left atrial appendage (LAA) closure compared with long-term warfarin therapy.BackgroundLAA closure is an alternative approach to chronic oral anticoagulation for the prevention of thromboembolism in patients with atrial fibrillation (AF).MethodsWe conducted a pooled, patient-level analysis of the 2 randomized clinical trials that compared WATCHMAN (Boston Scientific, Natick, Massachusetts) LAA closure with long-term warfarin therapy in AF.ResultsA total of 1,114 patients were included, with a median follow-up of 3.1 years. The overall rate of major bleeding from randomization to the end of follow-up was similar between treatment groups (3.5 events vs. 3.6 events per 100 patient-years; rate ratio [RR]: 0.96; 95% confidence interval [CI]: 0.66 to 1.40; p = 0.84). LAA closure significantly reduced bleeding >7 days post-randomization (1.8 events vs. 3.6 events per 100 patient-years; RR: 0.49; 95% CI: 0.32 to 0.75; p = 0.001), with the difference emerging 6 months after randomization (1.0 events vs. 3.5 events per 100 patient-years; RR: 0.28; 95% CI: 0.16 to 0.49; p < 0.001), when patients assigned to LAA closure were able to discontinue adjunctive oral anticoagulation and antiplatelet therapy. The reduction in bleeding with LAA closure was directionally consistent across all patient subgroups.ConclusionsThere was no difference in the overall rate of major bleeding in patients assigned to LAA closure compared with extended warfarin therapy over 3 years of follow-up. However, LAA closure significantly reduced bleeding beyond the procedural period, particularly once adjunctive pharmacotherapy was discontinued. The favorable effect of LAA closure on long-term bleeding should be considered when selecting a stroke prevention strategy for patients with nonvalvular AF. (WATCHMAN Left Atrial Appendage System for Embolic PROTECTion in Patients With Atrial Fibrillation; NCT00129545; and Evaluation of the WATCHMAN LAA Closure Device in Patients With Atrial Fibrillation Versus Long Term Warfarin Therapy [PREVAIL]; NCT01182441)     

Ileus is a predictor of local infection in patients with acute necrotizing pancreatitis

Background & objectivesInfected pancreatic necrosis (IPN) is associated with increased morbidity and mortality. Gut barrier dysfunction has been shown to increase the risk of bacterial translocation from the gut into the pancreatic bed. The primary aim of the study is to evaluate if ileus, a clinical marker of gut barrier dysfunction, can predict the development of IPN.MethodsA retrospective cohort study of patients with necrotizing pancreatitis (NP) was conducted from 2000 to 2014. Ileus was defined as ≥2 of the following criteria: nausea/vomiting; inability to tolerate a diet, absence of flatus, abdominal distension and features of ileus on imaging. Extensive necrosis was defined as >30% nonenhancing pancreatic parenchyma on contrast-enhanced CT. Multivariable cox proportional hazard analysis was used to evaluate known and potential predictors of IPN.Results142 patients were identified with NP, 61 with IPN and 81 with sterile necrosis. In comparison to a diagnosis of ileus documented in the medical chart, the ileus criteria had a sensitivity, specificity and positive and negative predictive value of 100%, 93%, 78% and 100%, respectively. On multivariate cox proportional hazard analysis, ileus [HR:2.6; 95%CI:1.4–4.9] and extensive necrosis [HR:2.8; 95%CI:1.3–5.8] were independently associated with the development of IPN while there was no association with bacteremia [HR:1.09; 95%CI:0.6–2.1].ConclusionIleus in NP can be accurately defined using surgical criteria. Ileus is independently associated with the future development of IPN. Further studies will be needed to determine if ileus can serve as a clinical marker to direct therapeutic interventions aimed at reducing the incidence of IPN.     

Efficacy of Polymer Injection for Ischemic Mitral Regurgitation: Persistent Reduction of Mitral Regurgitation and Attenuation of Left Ventricular Remodeling

ObjectivesThe aim of this study was to examine the chronic effects of polyvinyl-alcohol (PVA) injection on mitral regurgitation (MR) reduction, mitral valve geometry, and left ventricular (LV) remodeling in a chronic ischemic MR sheep model.BackgroundPrevious studies have demonstrated acute efficacy of PVA hydrogel polymer injection into infarcted myocardium underlying the papillary muscle to relieve MR by papillary muscle repositioning. However, the chronic efficacy of PVA injection in the chronic infarction setting remains unclear.MethodsSixteen sheep developed chronic MR 8 weeks after induced inferoposterior myocardial infarction. Ten consecutive sheep underwent PVA injection (PVA group) and 6 sheep served as control subjects with saline injection. Epicardial 2-/3-dimensional echocardiography was performed at the baseline, chronic MR (pre-injection), and sacrifice (8 weeks after injection) stages.ResultsBoth groups were comparable at the baseline and chronic MR stages. At sacrifice, MR decreased from moderate to trace or mild (vena contracta: 0.17 ± 0.08 cm vs. 0.56 ± 0.10 cm, p < 0.001) in the PVA group but progressed to moderate to severe in the control group. End-systolic and -diastolic volumes remained stable in the PVA group but increased significantly in the control group (both p < 0.05). At sacrifice, compared with the control group, the PVA group had significantly less left ventricular remodeling (end-systolic volume: 41.1 ± 10.4 ml vs. 55.9 ± 12.4 ml, p < 0.05), lower MR severity (vena contracta: 0.17 ± 0.08 cm vs. 0.60 ± 0.14 cm, p < 0.01), and favorable changes in mitral valve geometry.ConclusionsPolymer injection in a chronic ischemic MR model results in persistent reduction of MR and attenuation of continued left ventricular remodeling over 8 weeks of follow-up.     

Adult Left Ventricular Noncompaction: Reappraisal of Current Diagnostic Imaging Modalities

Left ventricular noncompaction (LVNC) cardiomyopathy is morphologically characterized by prominent myocardial trabeculations and deep recesses. The precise stage of development and the natural history of the disorder are not fully understood. Studies in heart failure patients demonstrate a high prevalence of myocardial trabeculations, raising the potential diagnosis of LVNC. Given the high prevalence compared with other primary cardiomyopathies, it is unclear whether the myocardial morphology is representative of LVNC or merely epiphenomena associated with increased cardiac pre-load. Imaging modalities including echocardiography and cardiac magnetic resonance imaging facilitate identification and assessment for LVNC; however, current diagnostic criteria are based on small cohorts and are liable to result in an overdiagnosis of LVNC. This review re-evaluates current diagnostic criteria and their potential impact on overdiagnosis of LVNC in low-risk populations.     

Relationship between QRS characteristics and delayed-enhancement cardiac magnetic resonance in patients with ischemic cardiomyopathy

BackgroundWe explored the relationship between QRS characteristics and myocardial phenotype by delayed-enhancement cardiac magnetic resonance (DE-CMR) in patients with coronary heart disease (CHD).Methods and resultsEighty five consecutive patients with CHD that were referred for DE-CMR evaluation constituted the study population. Of a total of 1445 left ventricular (LV) segments evaluated, 346 (23.9%) segments had fibrosis.Compared to patients without pathological Q waves, patients with pathological Q waves showed a higher number of segments with fibrosis (5.9 ± 3.1 vs. 2.7 ± 2.8, p < 0.001), and lower left ventricular ejection fraction (LVEF) (42.9 ± 13.6% vs. 51.8 ± 18.3, p = 0.01); whereas no significant differences were observed regarding LV size.When discriminated in according to the QRS duration tertiles, no significant differences were observed regarding the number of segments with fibrosis (p = 0.34), whereas the highest QRS tertile was related to the presence of a low LVEF (p = 0.005) and larger LV size (p = 0.01). QRS fragmentation (fQRS), defined as the presence of an R′ or notching in the nadir of the R wave or the S wave, or the presence of >1 R′ in 2 contiguous leads, was significantly related to LV size (LV end diastolic volume 153.6 ± 81.6 ml, vs. 111.5 ± 41.4 ml, p = 0.003), function (LVEF 43.2 ± 15.9% vs. 53.6 ± 16.3%, p = 0.005), and extent of fibrosis (5.1 ± 3.4 segments vs. 3.2 ± 3.1 segments, p = 0.01).ConclusionsIn the present study, fQRS was the only QRS-derived variable systematically and more closely related to LV size, LV systolic function, and to the presence and extent of fibrosis.     

Intravascular Ultrasound-Derived Minimal Lumen Area Criteria for Functionally Significant Left Main Coronary Artery Stenosis

ObjectivesThis study sought to evaluate the intravascular ultrasound (IVUS) minimal lumen area (MLA) for functionally significant left main coronary artery (LMCA) stenosis using fractional flow reserve (FFR) as the standard.BackgroundThe evaluation of significant LMCA stenosis remains challenging.MethodsWe identified 112 patients with isolated ostial and shaft intermediate LMCA stenosis (angiographic diameter stenosis of 30% to 80%) who underwent IVUS and FFR measurement.ResultsThe FFR was ≤0.80 in 66 LMCA lesions (59%); these exhibited smaller reference vessels, smaller minimal lumen diameter, greater diameter of stenosis, longer lesion length, smaller MLA, larger plaque burden, and more frequent plaque rupture. The independent factors of an FFR of ≤0.80 were plaque rupture (odds ratio [OR]: 4.47; 95% Confidence Interval (CI): 1.35 to 14.8; p = 0.014); body mass index (OR: 1.19; 95% CI: 1.00 to 1.41; p = 0.05), age (OR: 0.95; 95% CI: 0.90 to 1.00; p = 0.031), and IVUS MLA (OR: 0.37; 95% CI: 0.25 to 0.56; p < 0.001). The optimal IVUS MLA cutoff value for an FFR of ≤0.80 was 4.5 mm² (77% sensitivity, 82% specificity, 84% positive predictive value, 75% negative predictive value, area under the curve: 0.83, 95% CI: 0.76 to 0.96; p < 0.001) overall and 4.1 to 4.5 mm² in various subgroups. Adjustment for the body surface area, body mass index, and left ventricular mass did not improve the diagnostic accuracy of the IVUS MLA.ConclusionsIn patients with isolated ostial and shaft intermediate LMCA stenosis, an IVUS-derived MLA of ≤4.5 mm² is a useful index of an FFR of ≤0.80.