The association of imaging equipment age with other quality metrics and successful laboratory accreditation by the Intersocietal Accreditation Commission.

BACKGROUND: Intersocietal Accreditation Commission (IAC) accreditation is granted or delayed depending on the fulfillment of several quality metrics. Investing in up-to-date equipment might reflect a commitment to quality. METHODS: Data from echocardiography (n = 3079) and nuclear cardiology (n = 1835) accreditation applications submitted between 2012 and 2014 were evaluated to determine the mean age of laboratory equipment. Laboratory quality was assessed by the number of missing quality metrics, and a composite quality score was calculated as the sum of missing quality metrics. A lower score thus represented better laboratory quality. The relationship between equipment age and quality was explored as an interaction term between equipment age and the composite quality score and was incorporated into regression models for prediction of accreditation status. RESULTS: During the study period, 49% of echocardiography and 42% of nuclear laboratories were granted accreditation without delay. For both echocardiography and nuclear laboratories, there was a statistically significant trend toward an increasing number of missing quality metrics with increasing quartiles of equipment age. The interaction between equipment age and the composite quality score was a significant predictor of delay of accreditation for both echocardiography and nuclear cardiology laboratories, with a stronger association for 1st-time applicants. Among sites applying for accreditation in both modalities simultaneously, accreditation in one modality predicted the accreditation decision for the other. CONCLUSIONS: Laboratory quality is an important determinant of IAC accreditation, and equipment age is an effect modifier of this relationship. Contemporary equipment likely reflects a commitment to quality, for both echocardiography and nuclear laboratories.

Non-vitamin K oral anticoagulants versus warfarin for left atrial appendage thrombus resolution in nonvalvular atrial fibrillation or flutter.

BACKGROUND: Non-vitamin K oral anticoagulants (NOACs) have emerged as alternatives to vitamin K antagonists in select situations. For left atrial (LA) appendage thrombus in nonvalvular atrial fibrillation (AF) or flutter, guidelines recommend oral anticoagulation (OAC) for at least 3 weeks prior to reassessment. Data comparing NOACs to warfarin in this scenario are scarce. METHODS: A retrospective study identified subjects with nonvalvular AF or flutter who were: a) noted to have LA thrombus detected on transesophageal echocardiography (TEE), b) previously not receiving long-term OAC; and c) evaluated for resolution of LA thrombus by follow-up TEE between 3 weeks to less than 1 year of the initial TEE. RESULTS: The study included 45 subjects with mean age 63.2 years, 69% male, 78% white race/ethnicity, 42% paroxysmal, and mean CHA2 DS2 -VASc score 3.4 ± 1.7. All LA thrombi were confined to the appendage. OAC received included apixaban (3), dabigatran (13), rivaroxaban (6), and warfarin (23), The median follow-up time to repeat TEE was 67 (interquartile range, 49-96) days. LA appendage thrombus resolution rates were 76% for the entire cohort, 77% for NOACs, and 74% for warfarin. In univariable logistic regression analysis, LA appendage thrombus resolution was similar for NOACs when compared to warfarin (odds ratio, 1.20; 95% confidence interval, 0.31-4.69; P = .79). CONCLUSIONS: In patients nonvalvular AF or flutter who were OAC naïve at the time of diagnosis with LA appendage thrombus, complete resolution was similar between NOACs and warfarin.

In vivo functional assessment of a novel degradable metal and elastomeric scaffold-based tissue engineered heart valve.

OBJECTIVE: Ideal heart valve solutions aim to provide thrombosis-free durability. A scaffold-based polycarbonate urethane urea tissue-engineered heart valve designed to mimic native valve microstructure and function was used. This study examined the acute in vivo function of a stented tissue-engineered heart valve in a porcine model. METHODS: Trileaflet valves were fabricated by electrospinning polycarbonate urethane urea using double component fiber deposition. The tissue-engineered heart valve was mounted on an AZ31 magnesium alloy biodegradable stent frame. Five 80-kg Yorkshire pigs underwent open tissue-engineered heart valve implantation on cardiopulmonary bypass in the pulmonary position. Tissue-engineered heart valve function was echocardiographically evaluated immediately postimplant and at planned study end points at 1, 4, 8, and 12 hours. Explanted valves underwent biaxial mechanical testing and scanning electron microscopy for ultrastructural analysis and thrombosis detection. RESULTS: All 5 animals underwent successful valve implantation. All were weaned from cardiopulmonary bypass, closed, and recovered until harvest study end point except 1 animal that was found to have congenital tricuspid valve dysplasia and that was euthanized postimplant. All 5 cases revealed postcardiopulmonary bypass normal leaflet function, no regurgitation, and an average peak velocity of 2 m/s, unchanged at end point. All tissue-engineered heart valve leaflets retained microstructural architecture with no platelet activation or thrombosis by scanning electron microscopy. There was microscopic evidence of fibrin deposition on 2 of 5 stent frames, not on the tissue-engineered heart valve. Biaxial stress examination revealed retained postimplant mechanics of tissue-engineered heart valve fibers without functional or ultrastructural degradation. CONCLUSIONS: A biodegradable elastomeric heart valve scaffold for in situ tissue-engineered leaflet replacement is acutely functional and devoid of leaflet microthrombosis.

Oral anticoagulation and left atrial thrombi resolution in nonrheumatic atrial fibrillation or flutter: A systematic review and meta-analysis.

BACKGROUND: Oral anticoagulation (OAC) is prescribed for left atrial thrombi (LAT) in nonrheumatic atrial fibrillation (AF) and/or atrial flutter (AFL). The study objective was to review the existing evidence regarding LAT resolution in nonrheumatic AF and/or AFL with OAC agents. METHODS: Data sources included PubMed, EMBASE, and Cochrane Central Register of Controlled Trials (CENTRAL) between January 1, 1991 and February 10, 2017. English-language studies that assessed LAT resolution with OAC agents in subjects with nonrheumatic AF and/or AFL, by serial transesophageal echocardiography, and with follow-up times ≥ 3 weeks and < 1 year, were selected. Study quality was assessed using recommendations adapted from the Agency for Healthcare Research and Quality. Pooled LAT resolution rates were evaluated for vitamin K antagonist (VKA) studies and low risk of bias warfarin studies. RESULTS: The pooled LAT resolution rate of 619 subjects from 16 VKA studies was 63.7% (95% confidence interval [CI], 53.3%-72.9%). The pooled LAT resolution rate of 94 subjects from four studies that specified warfarin use, exclusion of prior long-term therapeutic OAC, and target international normalized ratio (INR) ≥ 2.0 and/or average achieved INR ≥ 2.0 was 79.3% (95% CI, 69.8%-86.4%). Two studies in direct-acting oral anticoagulants (DOACs) reported LAT resolution rates of 89.5% (17 of 19) for dabigatran and 41.5% (22 of 53) for rivaroxaban. CONCLUSIONS: Warfarin is the most studied initial OAC agent for treating LAT in nonrheumatic AF and/or AFL with a resolution rate of nearly 80%. Further studies in DOACs are warranted.

Outcomes of persistent pulmonary hypertension following transcatheter aortic valve replacement.

OBJECTIVES: To determine the prevalence and factors associated with persistent pulmonary hypertension (PH) following transcatheter aortic valve replacement (TAVR) and its relationship with long-term mortality. METHODS: Consecutive patients who underwent TAVR from July 2011 through January 2016 were studied. The prevalence of baseline PH (mean pulmonary artery pressure ≥25 mm Hg on right heart catheterisation) and the prevalence and the predictors of persistent≥moderate PH (pulmonary artery systolic pressure (PASP)>45 mm Hg on 1 month post-TAVR transthoracic Doppler echocardiography) were collected. Cox models quantified the effect of persistent PH on subsequent mortality while adjusting for confounders. RESULTS: Of the 407 TAVR patients, 273 (67%) had PH at baseline. Of these, 102 (25%) had persistent≥moderate PH. Mortality at 2 years in patients with no baseline PH versus those with PH improvement (follow-up PASP≤45 mm Hg) versus those with persistent≥moderate PH was 15.4%, 16.6% and 31.3%, respectively (p=0.049). After adjusting for Society of Thoracic Surgeons Predicted Risk of Mortality and baseline right ventricular function (using tricuspid annular plane systolic excursion), persistent≥moderate PH remained associated with all-cause mortality (HR=1.82, 95% CI 1.06 to 3.12, p=0.03). Baseline characteristics associated with increased likelihood of persistent≥moderate PH were ≥moderate tricuspid regurgitation, ≥moderate mitral regurgitation, atrial fibrillation/flutter, early (E) to late (A) ventricular filling velocities (E/A ratio) and left atrial volume index. CONCLUSIONS: Persistency of even moderate or greater PH at 1 month post-TAVR is common and associated with higher all-cause mortality.

Echocardiographic evaluation and guidance for MitraClip procedure.

Transcatheter mitral valve repair using the MitraClip system (Abbott, Abbott Park, Il, USA) has become a world-wide, well-established therapeutic alternative to treat symptomatic patients with severe mitral regurgitation and prohibitive surgical risk. This article offers a comprehensive review of the important clinical and imaging aspects related to the patient selection, imaging evaluation and intraprocedural guidance for optimal results using this transcatheter device therapy. This article provides an updated framework for the interested practitioners summarizing the current understanding and applications for this device based on the current literature and growing experience of this technique.

Right Ventricular Function and Prognosis in Patients with Low-Flow, Low-Gradient Severe Aortic Stenosis.

BACKGROUND: Patients with low left ventricular ejection fractions and low-flow, low-gradient aortic stenosis (AS) represent a challenging cohort with high morbidity and mortality. The prevalence and clinical impact of right ventricular dysfunction (RVD) on risk stratification and prognosis in these patients is unknown. METHODS: A retrospective analysis was performed of 65 patients with low-flow, low-gradient AS who underwent low-dose dobutamine stress echocardiography to determine AS severity and to ascertain flow reserve status (≥20% stroke volume increase). Clinical, demographic, and imaging data were prospectively collected. Per guidelines, RVD was defined as tricuspid annular plane systolic excursion < 16 mm in the apical four-chamber view and measured at baseline. Cox proportional hazards modeling was used to risk-adjust comparisons for the end point of all-cause mortality. RESULTS: The mean age was 74 ± 9 years, the mean left ventricular ejection fraction was 29 ± 10%, the mean indexed aortic valve (AV) area was 0.49 ± 0.1 cm(2)/m(2), and the mean AV gradient 22 ± 7 mm Hg. RVD was present in 37 patients (57% of the study cohort). After a median follow-up period of 13 months (interquartile range, 5-30 months), there were 29 AV replacements and 30 deaths. The presence of RVD (hazard ratio, 2.86; 95% CI, 1.21-6.75; P = .02) was an independent risk factor associated with all-cause mortality despite many adjustments for potential clinical and echocardiographic confounders such as AV replacement, Society of Thoracic Surgeons Predicted Risk of Mortality score, severity of tricuspid regurgitation, and left ventricular global longitudinal strain. CONCLUSIONS: Baseline RVD is prevalent in patients with low-flow, low-gradient AS undergoing dobutamine stress echocardiography. Quantification of right ventricular systolic function in these complex patients provides important prognostic value and risk stratification adjunctive to Society of Thoracic Surgeons Predicted Risk of Mortality score and should be incorporated into the decision-making process.

Natural progression of low-gradient severe aortic stenosis with preserved ejection fraction.

Because the natural progression of low-gradient aortic stenosis (LGAS) has not been well defined, we performed a retrospective study of 116 consecutive patients with aortic stenosis who had undergone follow-up echocardiography at a median interval of 698 days (range, 371-1,020 d). All patients had preserved left ventricular ejection fraction (>0.50) during and after follow-up. At baseline, patients were classified by aortic valve area (AVA) as having mild stenosis (≥1.5 cm(2)), moderate stenosis (≥1 to <1.5 cm(2)), or severe stenosis (<1 cm(2)). Severe aortic stenosis was further classified by mean gradient (LGAS, mean <40 mmHg; high-gradient aortic stenosis [HGAS], mean ≥40 mmHg). We compared baseline and follow-up values among 4 groups: patients with mild stenosis, moderate stenosis, LGAS, and HGAS. At baseline, 30 patients had mild stenosis, 54 had moderate stenosis, 24 had LGAS, and 8 had HGAS. Compared with the moderate group, the LGAS group had lower AVA but similar mean gradient. Yet the actuarial curves for progressing to HGAS were significantly different: 25% of patients in LGAS reached HGAS status significantly earlier than did 25% of patients in the moderate-AS group (713 vs 881 d; P=0.035). Because LGAS has a high propensity to progress to HGAS, we propose that low-gradient aortic stenosis patients be closely monitored as a distinct subgroup that warrants more frequent echocardiographic follow-up.

Echocardiographic sizing of the left atrium of the transplanted heart.

BACKGROUND: The left atrium (LA) in the transplanted heart (TH) is a surgically created chamber from variable portions of donor and recipient LA. The American Society of Echocardiography (ASE) recommends measuring LA size in native hearts using biplane LA volume index (LAVI) as a more accurate measurement than LA anterior-posterior diameter (LA-APD). We hypothesized that LA-APD underestimates LA size when compared with LAVI in the TH. METHODS: Patients with a TH from 1/05 to 1/10 who had a transthoracic echocardiogram within 24 months of transplant were studied. Patients were excluded if they had an ejection fraction <50%, left ventricular hypertrophy, >mild aortic or mitral regurgitation, or poor image quality. Echocardiograms were analyzed for LA-APD and LAVI. LA size was classified as normal, mild, moderate, or severely enlarged based on age and sex specific cutoffs per the ASE. RESULTS: Of 297 patients evaluated, 160 met inclusion criteria. Mean age was 57 ± 13 years and 79% were males. Mean LA-APD and LAVI were 4.3 ± 0.6 cm and 36 ± 14 mL/m(2), respectively. LAVI correlated with LA-APD (r = 0.43, R(2) = 0.18, P < 0.0001). By LA-APD measurement, 20 (13%) LA were classified as having moderate or severe LA enlargement versus 80 (50%) by LAVI, P = 0.001. LA size was underclassified by ≥ 2 classes in 44 (28%) by LA-APD versus LAVI. CONCLUSIONS: In the setting of cardiac transplant, the LA size classified by LA-APD is commonly less than that classified by LAVI.

Morbid obesity: obscuring the diagnosis of aortic stenosis in a patient with cardiogenic wheezing.

We report the case of a morbidly obese 65-year-old female who presented with repeated hypotensive episodes following dialysis. She was misdiagnosed as suffering from asthma, and eventually was found to have severe aortic stenosis. Obesity has become a common and formidable obstacle to gathering important diagnostic information in patients. Modern diagnostic lab tests and imaging modalities such as transthoracic echocardiography (TTE) can provide spurious data in the morbidly obese population, which can ultimately lead to misdiagnosis. In this clinical vignette, we discuss the relationship between the basic pathophysiologic mechanisms underlying aortic stenosis and patient clinical presentation. We also review the relevant literature and discuss the impact of obesity on the diagnosis of this condition.

Role of baseline echocardiography in the preoperative management of liver transplant candidates.

Liver transplantation (LT) has not traditionally been offered to patients with intracardiac shunts (ICSs) or pulmonary hypertension (PH). There is a paucity of data regarding cardiac structural characteristics in LT candidates. We examined echocardiographic characteristics and their role in managing LT candidates diagnosed with ICS and PH. We identified 502 consecutive patients (318 men, mean age 55 ± 11 years) who underwent LT and had preoperative echocardiogram. Demographics, cardiovascular risk factors, and echocardiographic variables were recorded and data were analyzed for end-stage liver disease diagnosis. ICSs were diagnosed with contrast echocardiography and PH was defined as estimated pulmonary artery systolic pressure >40 mm Hg. Primary end points included short-term (30-day) and long-term (mean 41-month) mortalities and the correlation between pre- and perioperative stroke. In our studied population >50% had >2 cardiovascular risk factors and with increasing frequency ICSs were diagnosed in 16%, PH in 25%, and intrapulmonary shunts in 41% of LT candidates. There was no correlation between short- and long-term mortality and ICS (p = 0.71 and 0.76, respectively) or PH (p = 0.79 and 0.71). Importantly, in those with ICS, no strokes occurred. In conclusion, structural differences exist between various end-stage liver disease diagnoses. ICSs diagnosed by echocardiography are not associated with an increased risk of perioperative stroke or increased mortality. A diagnosis of mild or moderate PH on baseline echocardiogram is not associated with worse outcomes and requires further assessment. Based on these findings, patients should not be excluded from consideration for LT based solely on the presence of an ICS or PH.

Neoplastic pericardial effusion.

Neoplastic pericardial effusion is a serious and common clinical disorder encountered by cardiologists, cardiothoracic surgeons, oncologists, and radiation oncologists. It may develop from direct extension or metastatic spread of the underlying malignancy, from an opportunistic infection, or from a complication of radiation therapy or chemotherapeutic toxicity. The clinical presentation varies, and the patient may be hemodynamically unstable in the setting of constrictive pericarditis and cardiac tamponade. The management depends on the patient's prognosis and varies from pericardiocentesis, sclerotherapy, and balloon pericardiotomy to cardiothoracic surgery. Patients with neoplastic pericardial effusion face a grave prognosis, as their malignancy is usually more advanced. This review article discusses the epidemiology and etiology, pathophysiology, clinical presentation, diagnosis, management, and prognosis of neoplastic pericardial effusion.

Acute aortic regurgitation secondary to disk embolization of a Björk-Shiley prosthetic aortic valve.

Having passed the 30th anniversary of the first implantation of a Björk-Shiley convexo-concave tilting mechanical valve, recognition of the life-threatening complication of strut fracture is not widespread. The authors report the case of a 48-year-old man with acute-onset chest pain and dyspnea found to have strut fracture and disk embolization of a 26-year-old Björk-Shiley prosthetic aortic valve. The value of echocardiography in the diagnosis of this condition is discussed.

Effect of bisphosphonates on the progression of degenerative aortic stenosis.

Bisphosphonates appear to regulate mineralization in both bone and vasculature. Degenerative aortic stenosis (AS) is thought to be due to vascular calcification. We studied the effect of bisphosphonates on the progression of degenerative AS. A retrospective study was performed on patients >70 years, who had transthoracic echocardiograms (TTE) >1 year apart and an initial aortic valve area (AVA) of 0.6-2.0 cm². Patients were excluded if they had an ejection fraction <40%, other significant valvular or congenital heart disease, end-stage renal disease or heart transplant. The cohort was divided depending on the use of bisphosphonates. Data were obtained by review of the TTE reports. AVA, peak and mean aortic valve gradient (AVG), and the change between the studies were calculated. Of 4,270 patients screened for AS, 76 patients fit study criteria with 8 in the bisphosphonate group and 68 in the nonbisphosphonate group. The period between the TTEs was 23 ± 5 months in both the groups. AVA in the nonbisphosphonate group worsened by 0.2 cm² and in the bisphosphonate group it improved by 0.1 cm² (P = 0.001 vs. nonbisphosphonate). The changes in peak and mean AVG between groups and compared to baseline were not significant. Bisphosphonates show promise for slowing the progression of degenerative AS.

Late bacterial endocarditis of an amplatzer atrial septal defect occluder device.

A 66-year-old man with a large secundum atrial septal defect (ASD) that had been repaired percutaneously 30 months previously with an Amplatzer ASD occluder (ASO) presented with fevers and Staphylococcus aureus bacteremia. Transesophageal echocardiography revealed a 1.5 x 1.5 cm mobile mass on the left atrial side of his ASO consistent with a vegetation. When the ASO was explanted, the left atrial side of the device was poorly endothelialized. In conclusion, the present report is the first description of late infective endocarditis in an adult with an ASO.

Beating-heart, off-pump mitral valve repair by implantation of artificial chordae tendineae: an acute in vivo animal study.

OBJECTIVE: To evaluate the effectiveness of a new off-pump mitral valve repair technology in restoring valve competency in a porcine model of acute mitral regurgitation. METHODS: Acute mitral regurgitation was induced in 6 anesthetized pigs by cutting anterior leaflet chordae. Artificial chordae were then transapically implanted on the prolapsing segment under epicardial echocardiographic guidance and secured outside the left ventricular apex. All intracardiac manipulations were performed off-pump, through a stab wound incision on the left ventricular apex. RESULTS: Cutting the anterior leaflet chordae caused an eccentric, posteriorly directed jet of mitral regurgitation that could be visualized by color Doppler sonography. Implantation of chordae through the left ventricular apex completely eliminated valve regurgitation in 4 animals and reduced regurgitation in 2. Intraoperative measurement of artificial chordal tensions gave similar values to those reported for native chordae. CONCLUSIONS: Off-pump, transapical implantation of artificial chordae between a prolapsing anterior mitral valve leaflet and the left ventricular apex was effective in reducing acutely induced mitral regurgitation. Long-term studies are planned to assess the stability in this animal model.