Artificial intelligence in echocardiography: Review and limitations including epistemological concerns.

BACKGROUND AND PURPOSE: In this review we describe the use of artificial intelligence in the field of echocardiography. Various aspects and terminologies used in artificial intelligence are explained in an easy-to-understand manner and supplemented with illustrations related to echocardiography. Limitations of artificial intelligence, including epistemologic concerns from a philosophical standpoint, are also discussed. METHODS: A narrative review of relevant papers was conducted. CONCLUSION: We provide an overview of the usefulness of artificial intelligence in echocardiography and focus on how it can supplement current day-to-day clinical practice in the assessment of various cardiovascular disease entities. On the other hand, there are significant limitations, including epistemological concerns, which need to be kept in perspective.

An analysis of the learning curve for robotic-assisted mitral valve repair.

BACKGROUND: Many cardiac surgeons receive training for sternotomy-based cardiac surgical operations in residency programs and only a few education programs offer training specifically in minimally invasive cardiac surgery. In this report, we aimed to search and analyze the learning curve for robotic-assisted mitral valve (MV) repair in cardiac surgeons. METHOD: Between January 2010 and July 2019, 60 robotic-assisted isolated MV repair surgeries were performed with DaVinci Robotic Systems in our center. Different kinds of surgical techniques were used. The assessment of the learning curve was based on cardiopulmonary bypass (CPB) and transthoracic aortic clamp (CC) times. RESULT: There were 23 (38.3%) men and 37 (61.7%) women with a mean age of 48.3 years. The lesions of the MV were posterior leaflet prolapsus (n = 42, 70.0%), anterior leaflet prolapsus (n = 8, 13.3%), Barlow disease (n = 3, 5%), and annular dilatation (n = 7, 11.6%). The patients underwent notochordal implantation (n = 27, 45%), quadrangular or triangular resection (n = 23, 38.3%), isolated ring annuloplasty (n = 7, 11.7%), resection, and leaflet reduction (n = 2, 3.3%) or edge to edge repair (n = 1, 1.7%). The maturation of the learning curve appeared to be about 30 cases. The statistical analysis showed that the mean CPB and CC times for the first 30 cases were greater compared with the 30 after learning curve (155.3 vs. 118.9 min [p = .00], 102.3 vs. 80 min [p = .00], respectively). There was no case of conversion to open surgery. No perioperative mortality was observed. CONCLUSION: The maturation of the learning curve for robotic-assisted MV repair appeared to be about 30 cases in our group of patients. This study had encouraging results for surgeons who desire to start a robotic mitral surgery program.

Easily measurable, noninvasive, and novel finding for pulmonary hypertension: Hypertrophy of the basal segment of septomarginal trabeculation of right ventricle.

BACKGROUND: Effect of pulmonary hypertension (PH) on right ventricular (RV) geometry constitutes an ideal target to assess both pulmonary artery pressure (PAP) and its physiological importance. In this study, we evaluated the diagnostic power of the basal segment of septomarginal trabeculation (SMT) in predicting the PH and RV hypertrophy by cardiovascular magnetic resonance (CMR) in patients with idiopathic pulmonary arterial hypertension (IPAH) and Eisenmenger's syndrome (ES). METHODS: Eleven patients with IPAH, seven patients with ES, and 20 healthy controls were enrolled. CMR was used to measure the area and the thickness of the basal segment of SMT and right ventricular free wall (RVFW). Pulmonary artery systolic pressures (PASPs) were estimated by transthoracic echocardiography (TTE) with continuous-wave Doppler analysis measuring maximal tricuspid regurgitation (TR) velocity. Late gadolinium enhancement (LGE) findings of CMR and brain natriuretic peptide (BNP) levels were also obtained in all patients and control group. RESULTS: The area and the thickness of the basal segment of SMT were higher in patients with IPAH and ES than control group (P<.001). Pulmonary artery dimension, end-diastolic diameter of RV, RVFW thickness, and BNP levels were found to be significantly correlated with PAP (P<.001). LGE was present at the insertion point of RV only in patients group (P<.001). CONCLUSIONS: Increased area and thickness of the basal segment of SMT are easily measurable noninvasive markers of PH in patients with IPAH and ES.

Pulmonary artery to aorta ratio for the detection of pulmonary hypertension: cardiovascular magnetic resonance and invasive hemodynamics in heart failure with preserved ejection fraction.

BACKGROUND: Previous work indicates that dilatation of the pulmonary artery (PA) itself or in relation to the ascending aorta (PA:Ao ratio) predicts pulmonary hypertension (PH). Whether these results also apply for heart failure with preserved ejection fraction (HFpEF) is unknown. In the present study we evaluated the diagnostic and prognostic power of PA diameter and PA:Ao ratio on top of right ventricular (RV) size, function, and septomarginal trabeculation (SMT) thickness by cardiovascular magnetic resonance (CMR) in HFpEF. METHODS AND RESULTS: 159 consecutive HFpEF patients were prospectively enrolled. Of these, 111 underwent CMR and invasive hemodynamic evaluation. By invasive assessment 64 % of patients suffered from moderate/severe PH (mean pulmonary artery pressure (mPAP) ≥30 mmHg). Significant differences between groups with and without moderate/severe PH were observed with respect to PA diameter (30.9 ± 5.1 mm versus 26 ± 5.1 mm, p < 0.001), PA:Ao ratio (0.93 ± 0.16 versus 0.78 ± 0.14, p < 0.001), and SMT diameter (4.6 ± 1.5 mm versus 3.8 ± 1.2 mm; p = 0.008). The strongest correlation with mPAP was found for PA:Ao ratio (r = 0.421, p < 0.001). By ROC analysis the best cut-off for the detection of moderate/severe PH was found for a PA:Ao ratio of 0.83. Patients were followed for 22.0 ± 14.9 months. By Kaplan Meier analysis event-free survival was significantly worse in patients with a PA:Ao ratio ≥0.83 (log rank, p = 0.004). By multivariable Cox-regression analysis PA:Ao ratio was independently associated with event-free survival (p = 0.003). CONCLUSION: PA:Ao ratio is an easily measureable noninvasive indicator for the presence and severity of PH in HFpEF, and it is related with outcome.

Comparison of Effects of Low- versus High-Dose Heparin on Access-Site Complications during Transradial Coronary Angiography: A Double-Blind Randomized Study.

OBJECTIVES: Although heparin is highly effective in reducing the rate of radial artery occlusion after transradial catheterization, the optimal heparin dose is still controversial. The aim of this study was to evaluate the efficacy and safety of two different heparin doses during transradial coronary angiography. METHODS: 490 consecutive patients undergoing transradial coronary angiography were prospectively enrolled into this double-blind randomized trial. A total of 202 patients enrolled in the low-dose (LD; 2,500 U of heparin) group and 202 patients enrolled in the high-dose (HD; 5,000 U of heparin) group were included in the final analysis. The primary endpoint of the study was radial artery occlusion. Bleeding and hematomas were the secondary outcome measures. RESULTS: At day 7, radial artery occlusion occurred in 5.9% of the patients in the LD group and in 5.4% of the patients in the HD group (p = 0.83). Bleeding during deflation of the transradial band occurred in 6.4% of the patients in the LD group and in 18.3% of the patients in the HD group; the difference was statistically significant (p < 0.001). Higher-dose heparin was found to be an independent predictor of bleeding (p = 0.007). CONCLUSION: A lower dose of heparin (i.e. 2,500 U) decreases bleeding during transradial band deflation without an increase in radial artery occlusion.

The relationship between epicardial adipose tissue and ST-segment resolution in patients with acute ST-segment elevation myocardial infarction undergoing primary percutaneous coronary intervention.

The relationship between epicardial adipose tissue (EAT) and coronary artery disease has been predominantly demonstrated in the last two decades. The aim of this study was to investigate the predictive value of EAT thickness on ST-segment resolution that reflects myocardial reperfusion in patients undergoing primary percutaneous coronary intervention (pPCI) for acute ST-segment elevation myocardial infarction (STEMI). The present study prospectively included 114 consecutive patients (mean age 54 ± 10 years, range 35-83, 15 women) with first acute STEMI who underwent successful pPCI. ST-segment resolution (ΔSTR) <70 % was accepted as ECG sign of no-reflow phenomenon. The EAT thickness was measured by two-dimensional echocardiography. EAT thickness was increased in patients with no-reflow (3.9 ± 1.7 vs. 5.4 ± 2, p = 0.001). EAT thickness was also found to be inversely correlated with ΔSTR (r = -0.414, p = 0.001). Multivariate logistic regression analysis demonstrated that EAT thickness independently predicted no-reflow (OR 1.43, 95 % CI 1.13-1.82, p = 0.003). Receiver operating characteristic curve analysis demonstrated good diagnostic accuracy for EAT thickness in predicting no-reflow [area under curve (AUC) = 0.72, 95 % CI 0.63-0.82, p < 0.001]. In conclusion, increased EAT thickness may play an important role in the prediction of no-reflow in STEMI treated with pPCI.

Jet length/velocity ratio: a new index for echocardiographic evaluation of chronic aortic regurgitation.

BACKGROUND: Management of aortic regurgitation depends on the assessment for severity. Echocardiography remains as the most widely available tool for evaluation of aortic regurgitation. In this manuscript, we describe a novel parameter, jet length/velocity ratio, for the diagnosis of severe aortic regurgitation. METHODS AND RESULTS: A total of 30 patients with aortic regurgitation were included to this study. Severity of aortic regurgitation was assessed with an aortic regurgitation index incorporating five echocardiographic parameters. Jet length/velocity ratio is calculated as the ratio of maximum jet penetrance to mean velocity of regurgitant flow. Jet length/velocity ratio was significantly higher in patients with severe aortic regurgitation (2.03 ± 0.53) compared to patients with less than severe aortic regurgitation (1.24 ± 0.32, P < 0.001). Correlation of jet length/velocity ratio with aortic regurgitation index was very good (r(2) = 0.86) and correlation coefficient was higher for jet length/velocity ratio compared to vena contracta, jet width/LVOT ratio and pressure half time. For a cutoff value of 1.61, jet length/velocity ratio had a sensitivity of 92% and specificity of 88%, with an AUC value of 0.955. CONCLUSIONS: Jet length/velocity ratio is a novel parameter that can be used to assess severity of chronic aortic regurgitation. Main limitation for usage of this novel parameter is jet impringement to left ventricular wall.

Efficacy of oral hydration in the prevention of contrast-induced acute kidney injury in patients undergoing coronary angiography or intervention.

BACKGROUND: Efficacy of intravenous (IV) volume expansion in preventing contrast-induced acute kidney injury (CI-AKI) is well known. However, the role of oral hydration has not been well established. The aim of this work was to evaluate the efficacy of oral hydration in preventing CI-AKI. METHODS: We prospectively randomized 225 patients undergoing coronary angiography and/or percutaneous coronary intervention in either oral hydration or IV hydration groups. Patients who have at least one of the high-risk factors for developing CI-AKI (advanced age, type 2 diabetes mellitus, anemia, hyperuricemia, a history of cardiac failure or systolic dysfunction) were included in the study. All patients had normal renal function or stage 1-2 chronic kidney disease. Patients in the oral hydration group were encouraged to drink unrestricted amounts of fluids freely whereas isotonic saline infusion was performed by the standard protocol in the IV hydration group. RESULTS: CI-AKI occurred in 8/116 patients (6.9%) in the oral hydration group and 8/109 patients (7.3%) in the IV hydration group (p = 0.89). There was also no statistically significant difference between the two groups when different CI-AKI definitions were taken into account. CONCLUSION: Oral hydration is as effective as IV hydration in preventing CI-AKI in patients with normal kidney function or stage 1-2 chronic kidney disease, and who also have at least one of the other high-risk factors for developing CI-AKI.

Diagnostic value of strain echocardiography, galectin-3, and tenascin-C levels for the identification of patients with pulmonary and cardiac sarcoidosis.

BACKGROUND: Cardiac involvement in sarcoidosis has been associated with poor prognosis. We evaluated myocardial contractility quantitatively in a cohort of pulmonary sarcoidosis (PS) patients with and without cardiac involvement. We also studied markers of fibrosis (tenascin-C [Tn-C] and galectin-3 [Gl-3]) as diagnostic tools for PS and cardiac sarcoidosis (CS). METHODS: Forty ambulatory patients with PS of grades 1-2 and 26 healthy subjects were prospectively enrolled. All patients with PS underwent cardiac magnetic resonance (CMR) to explore the presence of CS. The study population was divided into three groups: controls (n = 26), non-CS patients (n = 34), and CS patients (n = 6). Speckle-tracking strain echocardiography (STE) was performed on all patients, and Gl-3 and Tn-C values were measured in all patients and controls. RESULTS: PS patients had higher levels of Gl-3 and Tn-C than did controls, and the STE parameters of PS patients, including global longitudinal strain (GLS) and global circumferential strain (GCS), were lower than those of controls (p < 0.001 for all comparisons). GLS values were lower in CS patients than in the other groups (p = 0.05). CONCLUSIONS: PS patients demonstrate reduced cardiac contractility, independent of CMR-proven structural cardiac lesions, while patients with structural lesions have a more pronounced drop in strain parameters. Tn-C and Gl-3 are promising markers for the diagnosis of PS, but they are not specific for cardiac involvement.

Clinical staging in chronic heart failure associated with low vitamin D and elevated parathormone levels.

OBJECTIVE: Growing evidence in the literature suggests a relationship between heart failure and vitamin D-parathormone cascade. The aim of the present study was to investigate the association of the clinical stage of the heart failure with vitamin D-parathormone levels. METHODS AND RESULTS: Ninety consecutive patients, who were admitted to our clinic from December 2012 to May 2013, were included in the present study. The patients with heart failure were clinically classified into four stages (stage A through stage D). Vitamin D and parathormone levels were measured and echocardiographic recordings were obtained from each patient. The patients with heart failure had significantly lower vitamin D levels compared to the control group (14.5 ng/ml versus 38 ng/ml, P < 0.001). In the four subgroups of patients with heart failure, vitamin D levels significantly decreased (30 ng/ml, 25 ng/ml, 13.5 ng/ml, and 6 ng/ml in stages A, B, C, and D, respectively), and parathormone levels significantly increased (50 pq/ml, 44 pq/ml, 70 pq/ml, and 98.5 pg/ml, respectively) with progression in the heart failure from stage A to stage D (P < 0.001). The log10 EF (B = -2.39, 95% CI = -3.36-1.42, P < 0.001), log10 BNP (B = 0.405, 95% CI = 0.13-0.69, P = 0.005, log10 vitamin D (B = -0.75, 95% CI = -1.18-0.31, P = 0.001) were the independent predictors of heart failure stage in multivariate regression analysis. CONCLUSIONS: Vitamin D and parathormone levels were closely associated with the stage of heart failure. There was a significant decrease in vitamin D levels and a significant increase in serum parathormone levels with clinical deterioration in heart failure.

A rare manifestation of atrial fibrillation in the presence of Wolff-Parkinson-White syndrome: tachycardia-induced cardiomyopathy.

We report a 68-year-old man who presented with heart failure and atrial fibrillation (AF) with rapid ventricular response and wide QRS complexes. Tachycardia-induced cardiomyopathy (TIC) due to persistent AF developing on the basis of Wolff-Parkinson-White (WPW) syndrome was considered. Signs and symptoms of heart failure improved with restoration of sinus rhythm. This case suggested that persistent AF in a patient with WPW syndrome is one of the rare causes of TIC.

Echocardiography-guided or "sided" pericardiocentesis.

Echocardiography-guided pericardiocentesis is the first choice method for relieving cardiac tamponade, but the exact role of the echocardiography at the moment of the puncture is still controversial. In this report, detailed echocardiographic evaluation was performed in 21 consecutive patients with cardiac tamponade just before the pericardiocentesis. Appropriate needle position was determined according to the probe position using imaginary x, y, and z axes. Pericardiocentesis was performed successfully using this technique without simultaneous echocardiography and no complications were observed. We concluded that bedside echocardiography with detailed evaluation of the puncture site and angle is enough for pericardiocentesis instead of real time guiding.

Thrombus at ostium of coronary sinus discovered during evaluation for cardiac resynchronization therapy.

A 50-year-old male patient with dilated cardiomyopathy was evaluated for cardiac resynchronization therapy. A transthoracic echocardiogram revealed a mass in close proximity to the coronary sinus ostium.The mass was considered to be a thrombus and found to have disappeared at the repeat echocardiogram performed following a month of anticoagulation therapy with warfarin. In this case report, we aim to emphasize the importance of coronary sinus imaging, especially during echocardiographic evaluation for cardiac asynchrony.

Comparison of Pericardiocentesis in Post-Cardiac Surgery and Nonsurgical Patients with Pericardial Tamponade.

INTRODUCTION: There are several approaches for pericardiocentesis. However, there is no definite suggestion about puncture location after cardiac surgery. The purpose of this study is to examine whether there is any difference regarding puncture location during pericardiocentesis in postoperative cardiac tamponade comparing to nonsurgical cardiac tamponade. METHODS: We retrospectively analyzed patients who had undergone pericardiocentesis from August 2011 to December 2019. Patients were examined in two groups, nonsurgical and postsurgical, based on the etiology of pericardial tamponade. Clinical profiles, echocardiographic findings, and procedural outcomes were identified and compared. RESULTS: Sixty-eight pericardiocenteses were performed in this period. The etiology of pericardial effusion was cardiac surgery in 27 cases and nonsurgical medical conditions in 41 cases. Baseline demographic variables were similar between the surgical and nonsurgical groups. Loculated effusion was more common in the postsurgical group (48.1% vs. 4.9%, P<0.001). Maximal fluid locations were different between the groups; right ventricular location was more common in the nonsurgical group (36.6% vs. 11.1%, P=0.02), while lateral location was more common in the postsurgical group (12.2% vs. 40.7%, P=0.007). Apical drainage was more frequently performed in the postsurgical group compared to the nonsurgical group (77.8% vs. 53.7%, P=0.044). CONCLUSION: Apical approach as a puncture location can be used more frequently than subxiphoid approach for effusions occurred after cardiac surgery compared to nonsurgical effusions. Procedural success is prominent in this group and can be the first choice of treatment.

Association of changes in the infarct and remote zone myocardial tissue with cardiac remodeling after myocardial infarction: a T1 and T2 mapping study.

Tissue structure in the infarct and remote zone myocardium post-acute myocardial infarction (MI) may offer prognostic information concerning left ventricular remodeling. We aimed to identify or establish a relationship between adverse remodeling (AR) and changes (Δ) in T1, T2 mapping and extracellular volume (ECV) in post MI periods. Fifty-four MI patients underwent 3 Tesla CMR performed 2 weeks (acute phase) and 6 months post-MI. We measured T1 mapping with MOLLI sequences and T2 mapping with TrueFISP sequences. Hematocrit was quantified in scanning time. ECV was performed post-gadolinium enhancement. AR was defined as an increase of ≥ 10% in left ventricular end-diastolic volume in 6 months. In the acute phase post-MI, high T2 relaxation times of the infarct and remote zone myocardium were associated with AR (OR 1.15, p = 0.023 and OR 1.54, p = 0.002, respectively). There was a decrease in T2 relaxation times of the remote zone myocardium at 6 months in patients with AR (42.0 ± 4.0 vs. 39.0 ± 3.5 ms, p < 0.001), while insignificant difference was found in patients without AR. Increased ΔECV (%) and decreased remote ΔT2 values were associated with AR (OR 1.04, p = 0.043 and OR 0.77, p = 0.007, respectively). The diagnostic performance analysis in predicting AR showed that acute-phase remote T2 was similar to that of remote ΔT2 (p = 0.875) but was superior to that of ΔECV (%) (ΔAUC: 0.19 ± 0.09, p = 0.038). In both acute phase and change of 6 months post-MI, the T2 relaxation times in remote myocardium are independently associated with AR, and this suggests higher inflammation in the remote myocardium in the AR group than the other group, even though no significant pathophysiological difference was observed in the healing of the infarct zone between both groups.

Effects of isolated obesity on left and right ventricular function: a tissue Doppler and strain rate imaging study.

OBJECTIVE: To determine the subclinical effects of isolated obesity and its duration on cardiac function by using routine echocardiography and tissue Doppler myocardial strain rate. METHODS: Forty-nine subjects were enrolled in this study; 29 with isolated obesity defined as a body mass index > or = 30 kg/m(2) with no other cardiovascular comorbidities, and 20 nonobese controls. All subjects underwent two-dimensional and Doppler echocardiography including tissue Doppler imaging and myocardial strain rate. RESULTS: The average duration of obesity was 12.1 years (4-18 years). Abnormalities of left ventricular (LV) wall thickness, mass, diastolic function, and left atrial size were detected in obese individuals, despite having preserved ejection fractions. The LV global longitudinal peak strain rate was significantly lower in obese subjects compared to nonobese control subjects (1.07 +/- 0.14 vs. 1.38 +/- 0.12, P < 0.001). Using multivariate analysis, the duration of obesity (ss=-0.76, P < 0.001), body mass index (ss=-0.35, P = 0.023), and age (ss=-0.29, P = 0.009) were independent predictors of the decreased LV global longitudinal peak strain rate, while the duration of obesity (ss=-0.66, P < 0.001) and body mass index (ss=-0.28, P = 0.037) were independent predictors of the decreased right ventricular (RV) peak strain rate. CONCLUSION: The presence and the duration of obesity were associated with impairment of subclinical biventricular systolic and diastolic function. These findings have the potential to increase awareness of subclinical cardiac manifestations in patients with isolated obesity and influence their early management.

Usefulness of live/real time three-dimensional transthoracic echocardiography in evaluation of prosthetic valve function.

We studied 31 patients with prosthetic valves (PVs) using two-dimensional and three-dimensional transthorathic echocardiography (2DTTE and 3DTTE, respectively) in order to determine whether 3DTTE provides an incremental value on top of 2DTTE in the evaluation of these patients. With 3DTTE both leaflets of the St. Jude mechanical PV can be visualized simultaneously, thereby increasing the diagnostic confidence in excluding valvular abnormalities and overcoming the well-known limitations of 2DTTE in the examination of PVs, which heavily relies on Doppler. Three-dimensional transthorathic echocardiography provides a more comprehensive evaluation of PV regurgitation than 2DTTE with its ability to more precisely quantify PV regurgitation, in determining the mechanism causing regurgitation, and in localizing the regurgitant defect. Furthermore, 3DTTE is superior in identifying, quantifying, and localizing PV thrombi and vegetations, in addition to the unique feature of providing a look inside mass lesions by serial sectioning. These preliminary results suggest the superiority of 3DTTE over 2DTTE in the evaluation of PVs and that it provides incremental knowledge to the echocardiographer.

Comparative assessment of left atrial appendage by transesophageal and combined two- and three-dimensional transthoracic echocardiography.

OBJECTIVE: Our objective was to compare the utility of combined two-dimensional (2D) transthoracic echocardiography (TTE) and three-dimensional (3D) TTE versus 2D transesophageal echocardiography (TEE) in evaluation of the left atrium (LA) and LA appendage (LAA) for clot. BACKGROUND: 2DTEE, usually performed to visualize the LAA, is semi-invasive and not without risks. With improved technology the LAA has been increasingly visualized by 2DTTE and 3DTTE in many patients. METHODS: We compared combined 2DTTE and 3DTTE with 2DTEE in evaluating the LA/LAA for a thrombus. Ninety-two patients underwent 2DTTE, 3DTTE, and 2DTEE. An additional 20 patients, in whom TEE could not be performed, underwent 2DTTE and 3DTTE. RESULTS: LA and LAA could be visualized in all patients. Of 92 patients studied, 74 had no thrombus and 7 had thrombus in the LAA by all modalities. Eleven patients, 9 with atrial fibrillation (AF), had a suspected thrombus by 2DTEE, but 3DTTE cropping clearly showed these to be prominent pectinate muscles which were seen in short axis on 2DTEE as rounded echo dense masses and therefore mimicked thrombi. These 9 patients with AF underwent successful cardioversion without any complications. Of the 20 patients in whom TEE could not be performed, 19 had no thrombus in the LA/LAA and 1 had a clot in the LAA. These 19 patients underwent successful cardioversion without complications. CONCLUSIONS: Our preliminary study suggests that combined 2DTTE and 3DTTE has comparable accuracy to TEE in evaluating the LA and LAA for thrombus. In some patients TEE, but not 3DTTE, may misdiagnose pectinate musculature as thrombus.

Effect of alcohol-induced septal ablation on left atrial volume and ejection fraction assessed by real time three-dimensional transthoracic echocardiography in patients with hypertrophic cardiomyopathy.

Alcohol-induced septal ablation (AISA) is an accepted treatment for hypertrophic cardiomyopathy (HCM) patients with left ventricular (LV) outflow obstruction who are unresponsive to medical therapy. As left atrial (LA) enlargement has been correlated with increased morbidity and mortality in HCM, we assessed LA volumes and ejection fraction (EF) prior to and after AISA using real time three-dimensional (3D) transthoracic echocardiography (TTE) in 12 patients (9 women; mean age 52 +/- 15 years; 11 Caucasian). All patients underwent successful AISA with no complications and their resting left ventricular outflow gradients decreased from 40.5 +/- 22.2 to 9.1 +/- 17.6 mmHg (P < 0.001) while their gradients with provocation decreased from 126.2 +/- 31.7 to 21.8 +/- 28.0 mmHg (P < 0.001). All patients showed improvements in their New York Heart Association (NYHA) functional class. Both the LA end-systolic (45.2 +/- 12.9 to 37.2 +/- 13.7 ml, P < 0.0001) and end-diastolic (79.6 +/- 18.9 to 77.1 +/- 18.6 ml, P = 0.001) volumes decreased after AISA. The LA EF increased from 43.1 +/- 9.0 to 52.5 +/- 8.8% (P = 0.001). The increase in LA EF correlated with the decrease in the resting left ventricular outflow gradient (R =-0.647, P = 0.03). In conclusion, 3D echocardiography can be utilized to follow LA function after AISA for HCM. AISA results in clinical improvement in patients with HCM and in improvement of LA EF that is correlated with the decrease in the left ventricular outflow gradient.

Transthoracic Doppler echocardiographic coronary flow imaging in identification of left anterior descending coronary artery stenosis in patients with left bundle branch block.

BACKGROUND: Conventional noninvasive methods have well-known limitations for the detection of coronary artery disease (CAD) in patients with left bundle branch block (LBBB). However, advancements in Doppler echocardiography permit transthoracic imaging of coronary flow velocities (CFV) and measurement of coronary flow reserve (CFR). Our aim was to evaluate the diagnostic value of transthoracic CFR measurements for detection of significant left anterior descending (LAD) stenosis in patients with LBBB and compare it to that of myocardial perfusion scintigraphy (MPS). METHODS: Simultaneous transthoracic CFR measurements and MPS were analyzed in 44 consecutive patients with suspected CAD and permanent LBBB. Typical diastolic predominant phasic CFV Doppler spectra of distal LAD were obtained at rest and during a two-step (0.56-0.84 mg/kg) dipyridamole infusion protocol. CFR was defined as the ratio of peak hyperemic velocities to the baseline values. A reversible perfusion defect at LAD territory was accepted as a positive scintigraphy finding for significant LAD stenosis. A coronary angiography was performed within 5 days of the CFR studies. RESULTS: The hyperemic diastolic peak velocity (44 +/- 9 cm/sec vs 62 +/- 2 cm/sec; P=0.01) and diastolic CFR (1.38 +/- 0.17 vs 1.93 +/- 0.3; P=0.001) were significantly lower in patients with LAD stenosis compared to those without LAD stenosis. The diastolic CFR values of <1.6 yielded a sensitivity of 100% and a specificity of 94% in the identification of significant LAD stenosis. In comparison, MPS detected LAD stenosis with a sensitivity of 100% and a specificity of 29%. CONCLUSIONS: CFR measurement by transthoracic Doppler echocardiography is an accurate method that may improve noninvasive identification of LAD stenosis in patients with LBBB.