Improving the echocardiographic assessment of pulmonary pressure using the tricuspid regurgitant signal-The "chin" vs the "beard".

AIM: Transthoracic echocardiography (TTE) is a fundamental investigation for the noninvasive assessment of pulmonary hemodynamics and right heart function. The aim of this study was to assess the correlation and agreement of Doppler calculation of right ventricular systolic pressure (RVSP) and pulmonary vascular resistance (PVR) using "chin" and "beard" measurements of tricuspid regurgitant velocity (TRVmax ), with invasive pulmonary artery systolic pressure (PASP) and PVR. METHODS: One hundred patients undergoing right heart catheterisation (RHC) and near simultaneous transthoracic echocardiography were studied. TRVmax was recorded for "chin" measurement (distinct peak TRVmax signal) and where available (63 patients), "beard" measurement (higher indistinct peak TRVmax signal). RESULTS: Measurable TRV signal was obtained in 96 patients. Mean RVSPchin 54.7 ± 22.7 mm Hg and RVSPbeard 68.6 = 23 ± 26.3 mm Hg (P < .001). There was strong correlation between both RVSPchin and RVSPbeard with invasive PASP (Pearson's r = .9, R2  = 0.82, P < .001 - r = .88, R = .78, P < .001, respectively.). Bland-Altman analysis for RVSPchin and RVSPbeard showed a mean bias of -0.5 mm Hg (95% limits of agreement -21.4 to 20.5 mm Hg) and -10.7 (95% LOA -35.5 to 14.2 mm Hg), respectively. Receiver operator characteristics of TRVmax "chin" and "beard" for diagnosis of pulmonary hypertension was assessed with optimal cut-offs being 2.8 m/s (sensitivity 93%, specificity 87%) and 3.2 m/s (sensitivity 91%, specificity 82%), respectively. There was similar correlation between PVRchin and PVRbeard (r = .87, R2  = 0.75, P < .001 and r = .86, R2  = 0.74, P < .001, respectively). At higher PVR, there was overestimation of calculated PVR using PVRbeard . CONCLUSION: The accuracy of noninvasive measurement of right heart pressures is increased using the "chin" in estimation of both RVSP and PVR.

Feasibility of perflutren microsphere contrast transthoracic echocardiography in the visualization of ventricular endocardium during venovenous extracorporeal membrane oxygenation in a validated ovine model.

BACKGROUND: Transthoracic echocardiography (TTE) during extra corporeal membrane oxygenation (ECMO) is important but can be technically challenging. Contrast-specific TTE can improve imaging in suboptimal studies. These contrast microspheres are hydrodynamically labile structures. This study assessed the feasibility of contrast echocardiography (CE) during venovenous (VV) ECMO in a validated ovine model. METHOD: Twenty-four sheep were commenced on VV ECMO. Parasternal long-axis (Plax) and short-axis (Psax) views were obtained pre- and postcontrast while on VV ECMO. Endocardial definition scores (EDS) per segment were graded: 1 = good, 2 = suboptimal 3 = not seen. Endocardial border definition score index (EBDSI) was calculated for each view. Endocardial length (EL) in the Plax view for the left ventricle (LV) and right ventricle (RV) was measured. RESULTS: Summation EDS data for the LV and RV for unenhanced TTE (UE) versus CE TTE imaging: EDS 1 = 289 versus 346, EDS 2 = 38 versus 10, EDS 3 = 33 versus 4, respectively. Wilcoxon matched-pairs rank-sign tests showed a significant ranking difference (improvement) pre- and postcontrast for the LV (P < 0.0001), RV (P < 0.0001) and combined ventricular data (P < 0.0001). EBDSI for CE TTE was significantly lower than UE TTE for the LV (1.05 ± 0.17 vs. 1.22 ± 0.38, P = 0.0004) and RV (1.06 ± 0.22 vs. 1.42 ± 0.47, P = 0.0.0006) respectively. Visualized EL was significantly longer in CE versus UE for both the LV (58.6 ± 11.0 mm vs. 47.4 ± 11.7 mm, P < 0.0001) and the RV (52.3 ± 8.6 mm vs. 36.0 ± 13.1 mm, P < 0.0001), respectively. CONCLUSIONS: Despite exposure to destructive hydrodynamic forces, CE is a feasible technique in an ovine ECMO model. CE results in significantly improved EDS and increased EL.

The long-term outcomes of transcoronary ablation of septal hypertrophy compared to surgical myectomy in patients with symptomatic hypertrophic obstructive cardiomyopathy.

OBJECTIVES: The aim of this study was to compare the long-term outcomes of transcoronary ablation of septal hypertrophy (TASH) with open surgical myomectomy (SM) in patients with symptomatic hypertrophic obstructive cardiomyopathy (HOCM). METHODS: We reviewed patients who underwent either procedure at our institution. The demographics, clinical outcomes, echocardiographic parameters, and complications were compared. RESULTS: Seventy patients with HOCM were treated with either TASH (n = 47, 26 male) or SM (n = 23, 10 male). Compared to those treated with SM, patients undergoing TASH were older (57+/- 14.7 years versus 47 +/- 20.6 years, P = 0.021) and more symptomatic. A higher proportion of patients had syncope as a presenting feature in the TASH group compared to the SM group (57.5% vs. 17.4%, P = 0.002) respectively. They were also more likely to be in New York Heart Association (NYHA) class III/IV compared to the patients who underwent SM (85.1% vs. 39.1%; P < 0.001). Patients were followed for a mean period of 43 months (TASH) and 46 months (SM). Repeat procedures were more common in the TASH group (17% vs. 0%, P = 0.04) but mitral valve replacement was more common in the SM group (0% vs. 8.7%, P = 0.105). Symptom improvement, the rate of complications and all cause mortality rates were similar in both groups. CONCLUSIONS: TASH compares favorably with surgical myectomy with regard to symptom resolution, rate of complications and mortality in a tertiary referral centre and should be seen as an attractive alternative to surgical myectomy in the appropriate patient population.

The safety profile of perflutren microsphere contrast echocardiography during rest and stress imaging: results from an Australian multicentre cohort.

BACKGROUND: Contrast enhanced echocardiography (CEE) is utilised when sub-optimal image quality results in non-diagnostic echocardiograms. However, there have been numerous safety notices issued by regulatory authorities regarding rare but potentially serious adverse reactions (AR). This multi-centre, retrospective analysis was performed to assess the short-term safety of CEE in a broad range of indications. METHODS: All CEE performed over 58 months at three institutions were assessed for AR within 30 min. RESULTS: A total of 5956 CEE were performed in 5576 patients. A total of 4903 were stress CEE and 1053 resting CCE. Bolus administration in 5719, infusion in 237 cases; 89.9% of CCE were outpatients. Commonest CEE indication was functional stress testing (82.3%). There were 16 AR related to CEE (0.27%). All AR were mild, transient and all patients made a full recovery. No cases of serious anaphylaxis or death within 30 min of contrast administration. Comparing those with and without an AR, there were no significant differences in age, gender, BMI, LVEF, patient location, exam type or RVSP. There was a slightly increased likelihood of an AR during infusion versus bolus dosing (p = 0.02). CONCLUSION: CEE is a safe investigation in a broad range of indications and clinical scenarios. AR are very rare, mild and transient.

Early experience of transaortic TAVI--the future of surgical TAVI?

BACKGROUND: Trans-catheter aortic valve implantation (TAVI) is now a well recognised procedure for the high risk surgical patient with native or bioprosthetic aortic valve stenosis. Transfemoral and transapical implantation techniques are well described. With increasing referral of more marginal transapical patients, we describe our experience of a transaortic TAVI approach which we believe reduces the postoperative wound pain, respiratory complications, operative risk and hospital stay. METHODS: Patients referred for surgical TAVI underwent trans-catheter aortic valve implantation via an upper sternotomy and direct cannulation of the ascending aorta. RESULTS: Thirteen patients with a mean age of 81 years underwent transaortic Edwards SAPIEN valve implantation. There was no in hospital mortality in our series. One patient required insertion of a permanent pacemaker for complete heart block. There were no aortic cannulation complications. CONCLUSION: The transaortic TAVI approach provides good exposure of the distal ascending aorta, a familiar cannulation site for cardiac surgeons. Our initial experience demonstrates the approach to be a safe technique with the potential for faster and less complicated recovery in patients undergoing surgical TAVI procedures. With further experience and greater acceptance, the transaortic approach may ultimately become the procedure of choice for patients unsuitable for a transfemoral approach.

Update on echocardiography in the management of infective endocarditis.

Echocardiography is the major imaging modality used for the diagnosis of infective endocarditis (IE). It is also useful in detecting the complications of IE which often necessitate surgical intervention and strongly influence patient outcomes. Transesophageal echocardiography (TEE), with proven superiority over transthoracic echocardiography (TTE) for the detection of vegetations and complications such as abscess, should be performed in the vast majority of cases especially when TTE image quality is poor or implanted devices are present. Three-dimensional (3D) TEE provides enhanced display of anatomic-spatial relationships allowing more precise delineation of complex pathology, particularly of the mitral valve and annulus. Importantly, echocardiographic findings can be non-specific and should always be interpreted in the context of the pre-test probability of IE based on careful clinical assessment. IE remains a challenging disease associated with variable clinical presentations, and high mortality. Whenever IE is suspected, echocardiography should be utilized early for both diagnosis and detection of complications.

Genetic influences on right ventricular systolic pressure (RVSP) in chronic obstructive pulmonary disease (COPD).

BACKGROUND: Pulmonary hypertension (PH) is a complication of chronic obstructive pulmonary disease (COPD). This study examined genetic variations in mediators of vascular remodelling and their association with PH in patients with COPD. In patients with COPD, we genotyped 7 SNPs in 6 candidate PH genes (NOS3, ACE, EDN1, PTGIS, SLC6A4, VEGFA). We tested for association with right ventricular systolic pressure (RVSP), spirometry and gas transfer, and hypoxemia. METHODS: In patients with COPD, we genotyped 7 SNPs in 6 candidate PH genes (NOS3, ACE, EDN1, PTGIS, SLC6A4, VEGFA). We tested for association with right ventricular systolic pressure (RVSP), spirometry and gas transfer, and hypoxemia. RESULTS: 580 COPD patients were recruited, 341 patients had a transthoracic echocardiogram, with RVSP measurable in 278 patients (mean age 69 years, mean FEV1 50% predicted, mean RVSP 44 mmHg, median history of 50 pack-years). Of the 7 tested SNPs, the NOS3-VNTR polymorphism was significantly associated with RVSP in a dose-dependent fashion for the risk allele: mean RVSP for a/a and a/b genotypes were 52.0 and 46.6 mmHg respectively, compared to 43.2 mmHg for b/b genotypes (P = 0.032). No associations were found between RVSP and other polymorphisms. ACE II or ID genotypes were associated with a lower FEV1% predicted than the ACE DD genotype (P = 0.028). The NOS3-298 TT genotype was associated with lower KCO % predicted than the NOS3-298 GG or GT genotype (P = 0.031). CONCLUSIONS: The NOS3-VNTR polymorphism was associated with RVSP in patients with COPD, supporting its involvement in the pathogenesis of PH in COPD. ACE and NOS3 genotypes were associated with COPD disease severity, but not with the presence of PH. Further study of these genes could lead to the development of prognostic and screening tools for PH in COPD.

The use of computerised simulators for training of transthoracic and transoesophageal echocardiography. The future of echocardiographic training?

BACKGROUND: Echocardiography is the commonest form of non-invasive cardiac imaging but due to its methodology, it is operator dependent. Numerous advances in technology have resulted in the development of interactive programs and simulators to teach trainees the skills to perform particular procedures, including transthoracic and transoesophageal echocardiography. METHODS: Forty trainee sonographers assessed a computerised mannequin echocardiographic simulator and were taught how to obtain an apical two-chamber (A2C) view and image the superior vena cava (SVC). Forty-two attendees at a TOE simulator workshop assessed its utility and commented on perceived future use, using defined criteria. RESULTS: One hundred percent and 88% of sonographers found the simulator useful in obtaining the SVC or A2C view respectively. All users found it easy to use and the majority found it helped with image acquisition and interpretation. Attendees of the TOE training day assessed the simulator with 100% finding it easy to use, as well as the augmented reality graphics benefiting image acquisition. Ninety percent felt that it was realistic. CONCLUSIONS: This study revealed that both trainee sonographers and TOE proceduralists found the simulation process was realistic, helped in image acquisition and improved assessment of spatial relationships. Echocardiographic simulators may play an important role in the future training of echocardiographic skills.

The Prognostic Value of Echocardiographic Wall Motion Score Index in ST-Segment Elevation Myocardial Infarction.

Background: When compared to left ventricular ejection fraction (LVEF), previous studies have suggested the superiority of wall motion score index (WMSI) in predicting cardiac events in patients who have suffered acute myocardial infarction. However, there are limited studies assessing WMSI and mortality in ST-segment elevation myocardial infarction (STEMI). We aimed to compare the prognostic value of WMSI in a cohort of STEMI patients treated with primary percutaneous coronary intervention (PCI). Methods: A comparison of WMSI, LVEF, and all-cause mortality in STEMI patients treated with primary PCI between January 2008 and December 2020 was performed. The prognostic value of WMSI, LVEF, and traditional risk scores (TIMI, GRACE) were compared using multivariable logistic regression modelling. Results: Among 1181 patients, 27 died within 30-days (2.3%) and 49 died within 12 months (4.2%). WMSI ≥1.8 was associated with poorer survival at 12-months (9.2% vs 1.5%; p < 0.001). When used as the only classifier for predicting 12-month mortality, the discriminatory ability of WMSI (area under the curve (AUC): 0.77; 95% CI: 0.68-0.84) was significantly better than LVEF (AUC: 0.71; 95% CI: 0.61-0.79; p=0.034). After multivariable modelling, the AUC was comparable between models with either WMSI (AUC: 0.89; 95% CI: 0.85-0.94) or LVEF (AUC: 0.87; 95% CI: 0.83-0.92; p < 0.08) yet performed significantly better than TIMI (AUC: 0.71; 95% CI: 0.62-0.79; p < 0.001), or GRACE (AUC: 0.63; 95% CI: 0.54-0.71; p < 0.001) risk scores. Conclusions: When examined individually, WMSI is a superior predictor of 12-month mortality over LVEF in STEMI patients treated with primary PCI. When examined in multivariable predictive models, WMSI and LVEF perform very well at predicting 12-month mortality, especially when compared to existing STEMI risk scores.

Cardiovascular changes during maturation and ageing in male and female spontaneously hypertensive rats.

BACKGROUND: Cardiovascular remodeling leading to heart failure is common in the elderly. Testing effective pharmacological treatment of human heart failure requires a suitable animal model that adequately mimics the human disease state. METHODS: This study has characterized the structural, functional, and electrical characteristics of the cardiovascular system throughout the lifespan in male and female spontaneously hypertensive rats (SHRs), a genetic model of chronic hypertension-induced cardiovascular remodeling, and age- and gender-matched normotensive controls, to determine whether ageing SHRs mimic the changes seen in ageing humans. RESULTS: Both the ageing male and female SHRs developed progressive hypertension, ventricular hypertrophy, left ventricular fibrosis, action potential prolongation without impaired glucose tolerance. Male SHRs from 15 months of age exhibited left ventricular wall thinning and chamber dilation, together with systolic and diastolic dysfunction and increased cardiac stiffness and increased erythrocyte superoxide production, which were not present in the female SHRs. CONCLUSION: Ageing male SHRs in contrast to the female SHRs, better mimic the chronic heart failure in humans produced by chronic hypertension. Ageing male SHRs could then be used to investigate proposed therapeutic interventions for chronic congestive heart failure in humans.

Comparison of fluoroscopic versus real-time three-dimensional transthoracic echocardiographic guidance of endomyocardial biopsies.

AIMS: Fluoroscopic-guided right ventricular (RV) endomyocardial biopsy (EMBx) is the conventional method for obtaining myocardial samples to assess for rejection following heart transplantation. This study was designed to assess the feasibility and accuracy of guiding RV sheath and bioptome tip position using real-time three-dimensional echocardiography (RT3DE). METHODS AND RESULTS: Forty EMBx procedures were performed in 21 patients. Five procedures were in a native heart and 35 were performed following cardiac transplantation. A RV long sheath was positioned toward the mid to distal interventricular septum using fluoroscopy. RT3DE was used to correlate sheath tip position with fluoroscopic position. Bioptome tip visualization and position against the endocardium was assessed using RT3DE. Sheath tip location was repositioned in 18 cases (46%) following assessment using RT3DE, due to alignment toward the apex (9) and mid (5) or distal RV (4) free wall. The bioptome tip could be clearly visualized using RT3DE in 83% of passes. In 35% of passes, the bioptome tip was repositioned using RT3DE guidance to improve the sampling site. CONCLUSION: RT3DE-guided EMBx was feasible in the majority of patients and resulted in sheath repositioning in 46% of patients and bioptome tip reorientation in 35% of cases.

Left ventricular endocardial definition enhancement using perflutren microsphere contrast echocardiography during peripheral venoarterial extracorporeal membranous oxygenation.

Contrast echocardiography provides incremental benefit in patients with nondiagnostic imaging, particularly in the intensive care setting. There are minimal data regarding its use in patients on mechanical cardiac support devices. This case highlights the additional diagnostic information provided with contrast-enhanced imaging in a patient with shock, supported by a peripherally cannulated extra-corporeal membranous oxygenation (ECMO) device. The signal persistence was reduced compared to the conventional setting, as anticipated but the concentration of perflutren microspheres remained sufficient to provide satisfactory endocardial definition, despite passage through a centrifugal pump. There was no adverse affect on the patient's cardiorespiratory status or ECMO function.

Contrast echocardiography in Australian clinical practice.

BACKGROUND: The second-generation contrast agent Definity (a perflutren microsphere) became available in Australia in mid-2007. We describe the introduction of contrast echocardiography into a high-volume quaternary teaching hospital, performing over 16,000 echocardiograms per year. Workflow protocols were developed for patient selection, contrast administration, and image acquisition and analysis. METHODS: Data were prospectively collected for all contrast cases. Endocardial definition scores were derived by three independent observers before and after contrast administration, and statistically compared. RESULTS: 161 patients received contrast in the first 12 months of the contrast program. There was statistically significant improvement in endocardial definition scores after contrast administration (p=0.0001), and reduction in inter-observer variability of wall motion assessment. A number of clinically significant findings (pseudoaneurysm, non-compaction, thrombus) were detected on contrast echo that were not apparent on standard 2D imaging. Adverse events were rare (0.6%) with no life-threatening events. CONCLUSIONS: The introduction of a second-generation contrast agent into clinical workflow in a hospital echocardiography department resulted in a statistically significant improvement in endocardial definition, and safely provided diagnostic imaging in cases which were otherwise non-diagnostic. Inter-observer variability was reduced, and diagnostic yield increased. These results reflect previously published data, and indicate that contrast echocardiography is feasible in Australian clinical practice.

Mitral valve bio-prosthesis and annuloplasty thrombosis during extracorporeal membrane oxygenation: case series.

BACKGROUND: Veno-arterial extracorporeal membrane oxygenation (VA-ECMO) is a well-recognized form of haemodynamic support for patients with refractory cardiogenic shock, who are unable to be weaned off cardiopulmonary bypass. Thrombosis or bleeding from cannula sites or surgical wounds are the leading cause of morbidity and mortality in these patients, and presents a delicate balance of anticoagulation during management of patients undergoing circulatory support. CASE SUMMARY: In this case series, we discuss three cases of patients undergoing mitral valve replacements or repair with thrombosis of their new bio-prosthesis in the immediate post-operative setting. All three patients were supported with VA-ECMO post-operatively, and thrombosis occurred despite anticoagulation. DISCUSSION: During extracorporeal membrane oxygenation, the reduced flow throughout the heart increases the risk of intra-cardiac thrombosis. This is of particular importance in the context of mitral valve replacements and repairs, where the bio-prosthesis is an additional risk factor for thrombosis. Our cases demonstrate the morbidity and mortality of such complications, with the likely aetiology being low transvalvular flow in a newly inserted valve combined with the pro-thrombotic state created by the VA-ECMO circuit.

Direct visualization of septal perforator coronary arterial blood flow during perflutren microsphere contrast echocardiography.

A 62-year-old female with supraventricular tachycardia underwent a contrast echocardiogram to assess left ventricular structure and function due to sub-optimal images on conventional imaging. Multi-pulse, phase inversion, low mechanical index imaging was used (left ventricular opacification), combined with bolus dosing of a perflutren microsphere (Definity). In the parasternal short-axis view, during contrast imaging, flow within a septal coronary artery could be directly visualized. The corresponding coronary angiogram demonstrated prominent septal perforators arising from the LAD artery. By exploiting the non-linear oscillation properties of microbubbles and the linear oscillation properties of tissue, at low MI, contrast-specific imaging has the ability to enhance the contrast signal while suppressing the myocardial signal. This form of contrast imaging has high temporal and spatial resolution, enabling visualization of relatively small structures in real time. Clinical relevance of this finding includes the ability to enhance coronary blood flow evaluation, which would have utility in those studies where spectral Doppler is being used to evaluate coronary blood flow and coronary flow reserve and it may be beneficial in the identification of septal perforator arteries that should be injected with alcohol during percutaneous septal ablation for the management of hypertrophic obstructive cardiomyopathy.

Noninvasive cardiac output measurement in heart failure subjects on circulatory support.

BACKGROUND: Pulmonary artery catheter (PAC) thermodilution is commonly used in the perioperative cardiac surgical intensive care unit for measurement and management of central hemodynamics despite questions about effectiveness, difficulty of use, and safety. USCOM is a noninvasive continuous wave Doppler device for direct measurement of cardiac output (CO) and is an alternative to PAC. USCOM validation has predominantly been in the cardiac surgical intensive care unit against PAC, despite the recognized limitations in reliability of the method. We compared USCOM CO measurements with the CardioWest, an orthotopic total artificial heart (TAH), in heart failure (HF) subjects during controlled interventions. METHOD: CO, stroke volume (SV), and heart rate (HR) were measured in a blinded fashion using the CardioWest and the USCOM device in TAH HF patients. Five-hundred eight paired measures from 18 examinations of seven subjects were acquired as flow was varied by the CardioWest controller. Bland-Altman analysis was used to compare agreement. RESULTS: Mean values and standard deviations (+/-SD) for CO, SV, and HR by CardioWest and USCOM were 7.33 +/- 0.46 and 7.34 +/- 0.51 L/min, 56.2 +/- 3.8 and 56.6 +/- 3.8 mL, and 131 +/- 3 and 130 +/- 4 bpm, respectively. CO ranged from 5.2 to 9.3 L/min. The mean differences between methods for CO, SV, and HR were -0.01 +/- 0.23 L/min, -0.34 +/- 1.97 mL, and 0.9 +/- 2.3 bpm, respectively, with mean percentage differences of -0.3%, -0.6%, and 0.7%. The percentage limits of agreement for CO, SV, and HR were 6.4%, 7.1%, and 3.6%. DISCUSSION: USCOM is a feasible and accurate method for noninvasive measurement and monitoring of CO in TAH HF patients and may have a wider application in diagnosis and management of cardiovascular disease.

Congenital mitral stenosis by multimodality cardiac imaging.

This vignette illustrates a classic case of congenital mitral stenosis (Ruckman-VanPraagh type 1) presenting in adulthood and demonstrates the benefits of multimodality cardiac imaging prior to successful surgical intervention.

Echocardiographic assessment of myocardial function and mechanics during veno-venous extracorporeal membrane oxygenation.

BACKGROUND: Transthoracic echocardiography (TTE) plays a fundamental role in the management of patients supported with extra-corporeal membrane oxygenation (ECMO). In light of fluctuating clinical states, serial monitoring of cardiac function is required. Formal quantification of ventricular parameters and myocardial mechanics offer benefit over qualitative assessment. The aim of this research was to compare unenhanced (UE) versus contrast-enhanced (CE) quantification of myocardial function and mechanics during ECMO in a validated ovine model. METHODS: Twenty-four sheep were commenced on peripheral veno-venous ECMO. Acute smoke-induced lung injury was induced in 21 sheep (3 controls). CE-TTE with Definity using Cadence Pulse Sequencing was performed. Two readers performed image analysis with TomTec Arena. End diastolic area (EDA, cm2), end systolic area (ESA, cm2), fractional area change (FAC, %), endocardial global circumferential strain (EGCS, %), myocardial global circumferential strain (MGCS, %), endocardial rotation (ER, degrees) and global radial strain (GRD, %) were evaluated for UE-TTE and CE-TTE. RESULTS: Full data sets are available in 22 sheep (92%). Mean CE EDA and ESA were significantly larger than in unenhanced images. Mean FAC was almost identical between the two techniques. There was no significant difference between UE and CE EGCS, MGCS and ER. There was significant difference in GRS between imaging techniques. Unenhanced inter-observer variability was from 0.48-0.70 but significantly improved to 0.71-0.89 for contrast imaging in all echocardiographic parameters. CONCLUSION: Semi-automated methods of myocardial function and mechanics using CE-TTE during ECMO was feasible and similar to UE-TTE for all parameters except ventricular areas and global radial strain. Addition of contrast significantly decreased inter-observer variability of all measurements.

Radiation Exposure of Operators Performing Transesophageal Echocardiography During Percutaneous Structural Cardiac Interventions.

BACKGROUND: Transesophageal echocardiography operators (TEEOP) provide critical imaging support for percutaneous structural cardiac intervention procedures. They stand close to the patient and the associated scattered radiation. OBJECTIVES: This study sought to investigate TEEOP radiation dose during percutaneous structural cardiac intervention. METHODS: Key personnel (TEEOP, anesthetist, primary operator [OP1], and secondary operator) wore instantly downloadable personal dosimeters during procedures requiring TEE support. TEEOP effective dose (E) and E per unit Kerma area product (E/KAP) were calculated. E/KAP was compared with C-arm projections. Additional shielding for TEEOP was implemented, and doses were measured for a further 50 procedures. Multivariate linear regression was performed to investigate independent predictors of radiation dose reduction. RESULTS: In the initial 98 procedures, median TEEOP E was 2.62 µSv (interquartile range [IQR]: 0.95 to 4.76 µSv), similar to OP1 E: 1.91 µSv (IQR: 0.48 to 3.81 µSv) (p = 0.101), but significantly higher than secondary operator E: 0.48 µSv (IQR: 0.00 to 1.91 µSv) (p < 0.001) and anesthetist E: 0.48 µSv (IQR: 0.00 to 1.43 µSv) (p < 0.001). Procedures using predominantly right anterior oblique (RAO) and steep RAO projections were associated with high TEEOP E/KAP (p = 0.041). In a further 50 procedures, with additional TEEOP shielding, TEEOP E was reduced by 82% (2.62 µSv [IQR: 0.95 to 4.76] to 0.48 µSv [IQR: 0.00 to 1.43 µSv] [p < 0.001]). Multivariate regression demonstrated shielding, procedure type, and KAP as independent predictors of TEEOP dose. CONCLUSION: TEE operators are exposed to a radiation dose that is at least as high as that of OP1 during percutaneous cardiac intervention. Doses were higher with procedures using predominantly RAO projections. Radiation doses can be significantly reduced with the use of an additional ceiling-suspended lead shield.