Assessment of right ventricular function by transthoracic echocardiography following aortic valve replacement.

BACKGROUND: Tricuspid annular plane systolic excursion (TAPSE) is a widely used clinical measure of right ventricular (RV) systolic performance. However, postsurgical changes in the pattern of RV contraction may limit the utility of TAPSE for assessing global RV function. We retrospectively examined pre- and postoperative TAPSE and RV fractional area change (FAC) in patients undergoing 3 different types of aortic valve replacement (AVR). METHODS: Fifty-two patients enrolled in the Placement of AoRTic TraNscathetER Valve Trial at our institution were randomized to receive open AVR or transcatheter AVR (TAVR) by either the transapical or transfemoral access routes. Thirty-seven of these patients had analyzable transthoracic echocardiography (TTE) before and after AVR. Using M-mode echocardiography, TAPSE was measured in the apical four-chamber view. Using two-dimensional echocardiography, RV FAC was measured in the apical four-chamber view. RESULTS: The mean change in TAPSE was -0.7 ± 0.6 cm for open AVR (P = 0.002), -0.2 ± 0.4 cm for transapical TAVR (P = 0.26), and 0.1 ± 0.5 cm for transfemoral TAVR (P = 0.64). The mean change in RV FAC was -1 ± 5% for open AVR (P = 0.91), 2 ± 4% for transapical TAVR (P = 0.37), and 7 ± 10% for transfemoral TAVR (P = 0.07). CONCLUSIONS: The normal pattern of RV contraction was unchanged by transapical and transfemoral TAVR, while open AVR led to a significant decrease in TAPSE with preserved RV FAC. Thus, RV FAC is a preferable method for assessing RV function in the postoperative patient.

Clinical utility of automated assessment of left ventricular ejection fraction using artificial intelligence-assisted border detection.

BACKGROUND: Ejection fraction (EF) calculated from 2-dimensional echocardiography provides important prognostic and therapeutic information in patients with heart disease. However, quantification of EF requires planimetry and is time-consuming. As a result, visual assessment is frequently used but is subjective and requires extensive experience. New computer software to assess EF automatically is now available and could be used routinely in busy digital laboratories (>15,000 studies per year) and in core laboratories running large clinical trials. We tested Siemens AutoEF software (Siemens Medical Solutions, Erlangen, Germany) to determine whether it correlated with visual estimates of EF, manual planimetry, and cardiac magnetic resonance (CMR). METHODS: Siemens AutoEF is based on learned patterns and artificial intelligence. An expert and a novice reader assessed EF visually by reviewing transthoracic echocardiograms from consecutive patients. An experienced sonographer quantified EF in all studies using Simpson's method of disks. AutoEF results were compared to CMR. RESULTS: Ninety-two echocardiograms were analyzed. Visual assessment by the expert (R = 0.86) and the novice reader (R = 0.80) correlated more closely with manual planimetry using Simpson's method than did AutoEF (R = 0.64). The correlation between AutoEF and CMR was 0.63, 0.28, and 0.51 for EF, end-diastolic and end-systolic volumes, respectively. CONCLUSION: The discrepancies in EF estimates between AutoEF and manual tracing using Simpson's method and between AutoEF and CMR preclude routine clinical use of AutoEF until it has been validated in a number of large, busy echocardiographic laboratories. Visual assessment of EF, with its strong correlation with quantitative EF, underscores its continued clinical utility.

Failure of digital echocardiography to accurately diagnose intracardiac shunts.

BACKGROUND: Intravenous agitated saline injection during transthoracic echocardiography assists in the detection of right to left intracardiac and intrapulmonary shunts. Whether digital echocardiography offers comparable sensitivity and specificity to analog tape recording to assess shunts is unknown. Technical differences between methods could lead to significant differences in shunt detection. METHODS: Agitated saline was injected intravenously at rest and with Valsalva in 189 consecutive patient studies (406 injections). Echocardiographers assessed presence and degree of left ventricle contrast on simultaneously recorded analog tape and digital echocardiography images in blinded fashion. RESULTS: Digital echocardiography had low overall sensitivity (rest 0.50, valsalva 0.63, late 0.39) compared to analog tape. Longer clip lengths improved sensitivity for detection of late contrast passage (rest 0.50, valsalva 0.67, late 0.46). CONCLUSION: Digital echocardiography saline contrast studies have poor sensitivity for assessment of intracardiac shunts versus analog tape, and increasing clip length only modestly increases sensitivity. Joint Photographic Experts Group digital compression losses may be an important cause of failure to detect intracardiac shunts, including patent foramen ovale.

Effects of cardiac resynchronization therapy on ventricular remodeling.

Remodeling reflects the structural and functional deterioration that occurs in heart failure. Indices of remodeling constitute an important marker of the severity of heart failure, and reverse remodeling is an accepted goal in the treatment of heart failure. Cardiac resynchronization therapy (CRT) has been shown to reverse the remodeling process by improving ventricular size, shape, and mass and reducing mitral regurgitation in the short and long term. Diastolic function, right ventricular size, and atria exhibit reverse remodeling. Trials of medical therapy for heart failure strongly link remodeling indices with outcomes, and emerging data suggest that remodeling indices may be among the most accurate predictors of long-term morbidity and mortality in heart failure patients with CRT devices. This review discusses remodeling and focuses on the evidence for CRT-induced reverse remodeling.

Application of appropriateness criteria in outpatient transthoracic echocardiography.

BACKGROUND: Appropriateness criteria were applied to outpatient transthoracic echocardiographic (TTE) studies. METHODS: Indications were rated as appropriate, inappropriate, or unclassifiable, considering provider-stated indications, previous TTE studies, symptom changes, and patient-stated indications. Clinically important new or unexpected findings were recorded. RESULTS: Of 368 TTE studies, 206 (56%) were appropriate, 31 (8%) were inappropriate, and 131 (35%) were unclassifiable. Appropriateness was not correlated with patient or provider demographics. In 288 cases with prior TTE studies, there were 92 (32%) important new findings and 63 (22%) unexpected findings, of which 20% were from inappropriately ordered and 31% from unclassifiable TTE studies. Appropriateness was not associated with new (odds ratio, 1.23; 95% confidence interval, 0.48-3.18) or unexpected (odds ratio, 1.15; 95% confidence interval, 0.38-3.52) findings. Provider type and level of training were not correlated with new or unexpected findings. CONCLUSIONS: Many indications for TTE studies were unclassifiable. A high percentage of inappropriately ordered TTE studies yielded important information. Care must be taken in judging the value of TTE studies solely on the basis of appropriateness criteria.