Unmasking Obstruction in Hypertrophic Cardiomyopathy With Postprandial Resting and Treadmill Stress Echocardiography

BACKGROUND

Latent left ventricular outflow tract obstruction (LVOTO) is an important cause of symptoms in patients with hypertrophic cardiomyopathy (HCM) but can be challenging to provoke.

OBJECTIVES AND METHODS

To examine the value of postprandial resting and stress echocardiography and utilization of invasive or enhanced drug therapies (surgical myectomy, alcohol septal ablation, disopyramide, and mavacamten) in patients with postprandial LVOTO. Consecutive HCM patients without LVOTO underwent routine and postprandial echocardiography at rest, with provocation (Valsalva and standing) and after symptom-limited treadmill stress.

RESULTS

Among 252 patients (mean age, 58 years, 39% women), postprandial LVOT gradients were higher compared with routine echocardiography at rest (median, 9.0 [0-38.0] vs 0 [0-14.0] mm Hg; P < .0001) and with provocation (18.5 [0-70.3] vs 1.5 [0-41.0] mm Hg; P < .0001). Postprandial exercise stress echocardiogram (PPXSE) gradients were higher in a subset of 44 patients who underwent both postprandial and fasting stress echocardiography (47.0 [5.3-81.0] vs 17.5 [0-46.0] mm Hg; P < .0001). In total, 49 (19.5%) patients achieved the ≥50 mm Hg threshold under routine conditions (rest/provocation); 90 (35.7%) additional patients achieved postprandial gradients ≥50 mm Hg (rest/provocation/exercise), 38 (15.1%) with PPXSE alone. A total of 71 patients were treated with 91 invasive or enhanced drug therapies, 32 (45.1%) of whom had gradients ≥50 mm Hg only after eating (rest/provocation) and 8 (11.3%) only with PPXSE, with symptom relief in the majority.

CONCLUSIONS

Postprandial echocardiography was useful at unmasking LVOTO in more than one-third of patients who did not have high gradients otherwise. Eating before echocardiography is a powerful provocative tool in the evaluation of patients with HCM.

Comparing Management Strategies in Patients With Clot-in-Transit

BACKGROUND

Clot-in-transit is associated with high mortality, but optimal management strategies remain uncertain. The aim of this study was to compare the outcomes of different treatment strategies in patients with clot-in-transit.

METHODS

This is a retrospective study of patients with documented clot-in-transit in the right heart on echocardiography across 2 institutions between January 2020 and October 2023. The primary outcome was a composite of in-hospital mortality, resuscitated cardiac arrest, or hemodynamic decompensation.

RESULTS

Among 35 patients included in the study, 10 patients (28.6%) received anticoagulation alone and 2 patients (5.7%) received systemic thrombolysis, while 23 patients (65.7%) underwent catheter-based therapy (CBT; 22 mechanical thrombectomy and 1 catheter-directed thrombolysis). Over a median follow-up of 30 days, 9 patients (25.7%) experienced the primary composite outcome. Compared with anticoagulation alone, patients who received CBT or systemic thrombolysis had significantly lower rates of the primary composite outcome (12% versus 60%; log-rank P<0.001; hazard ratio, 0.13 [95% CI, 0.03-0.54]; P=0.005) including a lower rate of death (8% versus 50%; hazard ratio, 0.10 [95% CI, 0.02-0.55]; P=0.008), resuscitated cardiac arrest (4% versus 30%; hazard ratio, 0.12 [95% CI, 0.01-1.15]; P=0.067), or hemodynamic deterioration (4% versus 30%; hazard ratio, 0.12 [95% CI, 0.01-1.15]; P=0.067).

CONCLUSIONS

In this study of CBT in patients with clot-in-transit, CBT or systemic thrombolysis was associated with a significantly lower rate of adverse clinical outcomes, including a lower rate of death compared with anticoagulation alone driven by the CBT group. CBT has the potential to improve outcomes. Further large-scale studies are needed to test these associations.

Echocardiography in the Recognition and Management of Mechanical Complications of Acute Myocardial Infarction

PURPOSE OF REVIEW

Although rare, the development of mechanical complications following an acute myocardial infarction is associated with a high morbidity and mortality. Here, we review the clinical features, diagnostic strategy, and treatment options for each of the mechanical complications, with a focus on the role of echocardiography.

RECENT FINDINGS

The growth of percutaneous structural interventions worldwide has given rise to new non-surgical options for management of mechanical complications. As such, select patients may benefit from a novel use of these established treatment methods. A thorough understanding of the two-dimensional, three-dimensional, color Doppler, and spectral Doppler findings for each mechanical complication is essential in recognizing major causes of hemodynamic decompensation after an acute myocardial infarction. Thereafter, echocardiography can aid in the selection and maintenance of mechanical circulatory support and potentially facilitate the use of a percutaneous intervention.

Rheumatic Heart Disease: A Rare Cause of Very Severe Valvular Aortic Stenosis

•RHD is a rare cause of severe valvular AS. •Rheumatic MS typically accompanies rheumatic AV disease. •2D and 3D echocardiography are essential in the assessment of rheumatic AS. •CCT has become crucial in planning therapeutic procedures for AS.

A Case Report of Cardiac Arrest After Intravenous Administration of Sulfur Hexafluoride (Lumason®) Ultrasound Enhancing Agent

Ultrasound enhancing agents (UEAs) are medications that enable clear visualization of ultrasound images. While large studies have demonstrated the safety of these agents, case reports of life-threatening reactions temporally associated with their use have been published and reported to the Food and Drug Administration. Current literature describes the most serious adverse reactions due to UEAs to be allergic in nature; however, embolic phenomena may play a role as well. Here, we report a case of unexplained cardiac arrest following the administration of sulfur hexafluoride (Lumason®) in an adult inpatient undergoing echocardiography where resuscitative efforts were ultimately unsuccessful, and review possible mechanisms of cardiac arrest based on prior published literature.

Saddle Pulmonary Embolism Detected by Transthoracic Echocardiography in a Patient With Suspected Myocardial Infarction

•PE is very rarely identified on TTE. •Saddle PE does not represent a higher-risk subset of PE. •Catheter-based therapies are becoming more commonplace in the management of acute PE.

Anatomical/Physiological Correlates of Functional Capacity in Adults With Repaired and Nonsevere Coarctation of the Aorta

Background

There is limited data regarding the interplay of anatomic and physiologic parameters with exercise capacity in adults with native or recurrent nonsevere coarctation of the aorta (CoA).

Objectives

The objective of this study was to use exercise stress echocardiography and cardiac magnetic resonance imaging to identify anatomic and physiologic correlates of exercise capacity in these patients.

Methods

We conducted a single-center retrospective analysis of 54 adults with nonsevere CoA (repaired or unrepaired) followed at our institution between 2015 and 2020. Resting coarctation gradients were obtained using echocardiography. Exercise gradients and functional capacity were assessed using exercise stress echocardiography. Aorta anatomy was obtained using magnetic resonance imaging.

Results

Coarctation-to-diaphragm ratio correlated with minutes of exercise (r = 0.56, P < 0.01) and metabolic equivalents (r = 0.49, P < 0.01). These relationships remained significant after controlling for use of beta-blockers, valvular disease, and type of coarctation repair. Minutes of exercise correlated with mean resting gradients (r = -0.39, P < 0.05). Coarctation-to-diaphragm ratio correlated with peak and mean resting gradients (r = -0.34, P < 0.05; r = -0.48, P < 0.01). Patients with coarctation-to-diaphragm ratio ≤0.7 achieved fewer metabolic equivalents (11.1 ± 1.9 vs 12.8 ± 2.2, P < 0.05) and minutes of exercise (10.3 ± 2.0 vs 12.6 ± 2.7, P < 0.05).

Conclusions

In patients with nonsevere native or recurrent CoA, reduced exercise capacity is correlated with coarctation severity by anatomic size and gradients. Those with a coarctation-to-diaphragm ratio ≤0.7 may represent a subset of patients with nonsevere CoA whose clinical symptoms are only elicited with exercise stress testing. Exercise stress testing and cross-sectional imaging may help identify those who could be considered for earlier coarctation intervention.

Left Atrial Appendage Tilt-Up-and-Turn-Left Maneuver: A Novel Three-Dimensional Transesophageal Echocardiography Imaging Maneuver to Characterize the Left Atrial Appendage and to Improve Transcatheter Closure Guidance

•Precise LAA anatomy must be established for LAA occlusion device selection. •We have developed the TUPLE maneuver, an acronym for “tilt up and turn left”. •The TUPLE maneuver facilitates LAA device selection and intraprocedural guidance.

Concordance of Pericardial Effusion Size Between Computed Tomography and Echocardiography

Discrepancy between computed tomography (CT) and transthoracic echocardiography (TTE) regarding pericardial effusion (PEff) size is common, but there is limited data regarding the correlation between these 2 imaging methods. The aim of this study is to examine the real-world concordance of observed PEff size between CT and TTE. We performed a retrospective analysis of all imaging reports available from 2013 to 2019 and identified patients with a PEff who underwent both a chest CT and TTE within a 24-hour period. We evaluated the agreement between CT and TTE in assessing PEff size. Of 1,118 patients included in the study, mean age was 66 (±17 years) and 54% were female. The median time interval between the 2 studies was 9.4 hours (interquartile range 3.5 to 16.6). Patients within a half-grade or full-grade of agreement were 71.9% and 97.2%, respectively. The mean difference in grade of agreement (TTE minus CT) between the 2 imaging methods was -0.1 (±0.6, p <0.0001). CT was more likely to report a higher grade (i.e. larger PEff size) when compared with TTE (261 patients vs 157 patients, p <0.001). The weighted kappa was 0.73 (95% confidence interval 0.69 to 0.76). After excluding patients with trace/no effusion, 42.3% and 94.1% of patients' studies were within a half-grade or full-grade of agreement, respectively. Of the 18 patients who had large discrepancies, 9 patients had loculated effusions, 2 patients had large pleural effusions, and 6 patients had suboptimal TTEs images. In conclusion, TTE and CT showed relatively strong agreement in estimation of PEff size, with CT sizes larger than TTE, on average. Large discrepancies in size may be related to reduced image quality, large pleural effusions, and loculated PEff.

Cysts Around the Heart: Differential Diagnosis and Multimodality Imaging Strategies for Paracardiac Cysts

•Paracardiac cysts (located adjacent to or inside the heart) are rarely detected. •There is a broad differential diagnosis for cysts encountered with echocardiography. •Multimodality imaging is crucial for comprehensively evaluating paracardiac cysts.

The Double-Orifice Left Atrial Appendage: Multimodality and Virtual Transillumination Imaging

•LAA membranes are exceedingly rare with variable morphologies. •Thromboembolic risk with LAA membranes remains unknown. •Use of 3D TEE transillumination may assist in visualization and understanding.

Device-Associated Thrombus with Watchman FLX Left Atrial Appendage Closure Device: A Report of Two Cases

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Individual cases of Watchman FLX DAT are scare in literature.

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The Watchman FLX has shown lower rates of DAT than the Watchman 2.0.

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Thrombus formation is still possible in rare instances with the Watchman FLX.

Recommendations for Special Competency in Echocardiographic Guidance of Structural Heart Disease Interventions: From the American Society of Echocardiography

Transcatheter therapies for structural heart disease continue to grow at a rapid pace, and echocardiography is the primary imaging modality used to support such procedures. Transesophageal echocardiographic guidance of structural heart disease procedures must be performed by highly skilled echocardiographers who can provide rapid, accurate, and high-quality image acquisition and interpretation in real time. Training standards are needed to ensure that interventional echocardiographers have the necessary expertise to perform this complex task. This document provides guidance on all critical aspects of training for cardiology and anesthesiology trainees and postgraduate echocardiographers who plan to specialize in interventional echocardiography. Core competencies common to all transcatheter therapies are reviewed in addition to competencies for each specific transcatheter procedure. A core principle is that the length of interventional echocardiography training or achieved procedure volumes are less important than the demonstration of procedure-specific competencies within the milestone domains of knowledge, skill, and communication.

Apical Aneurysms and Mid-Left Ventricular Obstruction in Hypertrophic Cardiomyopathy

BACKGROUND

Apical left ventricular (LV) aneurysms in hypertrophic cardiomyopathy (HCM) are associated with adverse outcomes. The reported frequency of mid-LV obstruction has varied from 36% to 90%.

OBJECTIVES

The authors sought to ascertain the frequency of mid-LV obstruction in HCM apical aneurysms.

METHODS

The authors analyzed echocardiographic and cardiac magnetic resonance examinations of patients with aneurysms from 3 dedicated programs and compared them with 63 normal controls and 47 controls with apical-mid HCM who did not have aneurysms (22 with increased LV systolic velocities).

RESULTS

There were 108 patients with a mean age of 57.4 ± 13.5 years; 40 (37%) were women. One hundred three aneurysm patients (95%) had mid-LV obstruction with mid-LV complete systolic emptying. Of the patients with obstruction, 84% had a midsystolic Doppler signal void, a marker of complete flow cessation, but only 19% had Doppler systolic gradients ≥30 mm Hg. Five patients (5%) had relative hypokinesia in mid-LV without obstruction. Aneurysm size is not bimodal but appears distributed by power law, with large aneurysms decidedly less common. Comparing mid-LV obstruction aneurysm patients with all control groups, the short-axis (SAX) systolic areas were smaller (P < 0.007), the percent SAX area change was greater (P < 0.005), the papillary muscle (PM) areas were larger (P < 0.003), and the diastolic PM areas/SAX diastolic areas were greater (P < 0.005). Patients with aneurysms had 22% greater SAX PM areas compared with those with elevated LV velocities but no aneurysms (median: 3.00 cm² [IQR: 2.38-3.70 cm²] vs 2.45 [IQR: 1.81-2.95 cm²]; P = 0.004). Complete emptying occurs circumferentially around central PMs that contribute to obstruction. Late gadolinium enhancement was always brightest and the most transmural apical of, or at the level of, complete emptying.

CONCLUSIONS

The great majority (95%) of patients in the continuum of apical aneurysms have associated mid-LV obstruction. Further research to investigate obstruction as a contributing cause to apical aneurysms is warranted.

Taking Command of Three-Dimensional Stitching Artifacts: From an Annoyance to an Easy Tool for Navigating Three-Dimensional Transesophageal Echocardiography

Despite many recent advances in three-dimensional (3D) transesophageal echocardiography (TEE) imagining, the process of orienting 3D TEE images is nonintuitive and uses assumptions based on idealized anatomy. Correlating two-dimensional TEE cross-sectional images to 3D reconstructions remains an additional challenge. In this article, we suggest the repurposing of the stitching artifact generated in 2-beat electrocardiogram-gated 3D TEE as a means of exactly orienting 3D images within a patient's unique anatomy. We demonstrate the application of this strategy to assess a normal mitral valve to localize scallops of mitral valve prolapse and to visualize typical left atrial appendage two-dimensional cuts in a 3D space. By taking command of stitching artifacts, cardiac imagers can successfully navigate the complex structures of the heart for optimal, individualized echocardiographic views.

Bacterial endocarditis with AACEK (HACEK) organisms

INTRODUCTION

Gram-negative organisms of the AACEK group, formerly known as HACEK, rarely cause endocarditis.

CASE SERIES

We present three cases of bacterial endocarditis, involving native and prosthetic valves, caused by AACEK organisms. In two patients, Cardiobacterium hominis was the responsible organism, and in a third, Aggregatibacter aphrophilus was implicated. A dental source of infection was identified in two patients, and in all three patients, the presentation of endocarditis was subacute.

DISCUSSION

This case series highlights the indolent nature of infection with the AACEK organisms. It also demonstrates the crucial role of multimodality imaging, especially transesophageal echocardiography, in the diagnosis of AACEk endocarditis of both native and prosthetic valves, and in delineating the extent of abscess in those with prosthetic valve infection.

Multimodality Imaging of Caval and Coronary Sinus Venous Anomalies

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Abnormal fetal development can produce several anomalies of the caval venous system.

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We present multimodality imaging of the most common caval venous anomalies.

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Each imaging modality provides incremental value when identifying these anomalies.

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Even normal variants may impact pacing lead or central venous catheter placement.

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Pathologic variants may lead to intracardiac shunting.

Multimodality Imaging of Sinus Venosus Atrial Septal Defect: A Challenging Diagnosis in Adults

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SVASD should be suspected in cases of unexplained RV volume overload.

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Direct visualization of SVASD with TTE is difficult in adults compared with children.

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TEE is helpful for diagnosing SVASD and associated pulmonary venous abnormalities.

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Multimodal imaging techniques offer incremental value in the workup of SVASD.