Aims: Aorto-left ventricular tunnel (ALVT) has typically been reported in infants rather than in adults.Transesophageal echocardiogram (TEE) appears to be a promising method of recognizing the spatial relationship of intracardiac structures and can produce higher quality images than transthoracic echocardiogram (TTE).The aim of this study was to compare the diagnostic accuracy of combined 2-dimensional (2D) and real-time three-dimensional (RT-3D) TEE imaging with the anatomic findings during surgery in adults with ALVT.Methods Ten patients diagnosed by conventional outpatient TTE with ALVT (n=6) or ruptured sinus of Valsalva (n=4) underwent further evaluation with both 2D and RT-3D TEE preoperatively and intraoperatively in Xinqiao Hospital Chongqing from May 2010 to August 2013.Their clinical, echocardiographic, and surgical details were reported.None of the patients had a history of endocarditis.This study was approved by the Xinqiao Hospital Clinical Research Ethics Committee.All patients underwent comprehensive 2D and RT-3D TEE examinations.An echocardiogram was performed using a Philips IE 33 ultrasound system with a matrix-array 3D transesophageal echocardiographic probe (X7-2t;Philips Medical System, Boston, MA, USA).ALVT was diagnosed according to the guidelines described by Levy in 1963.1 ALVT was defined as follows8: type Ⅰ, a simple tunnel with a slit-like opening at the aortic end and no aortic valve distortion;type Ⅱ, a large extracardiac aortic wall aneurysm of the tunnel with an oval opening at the aortic end, with or without valvular distortion;type Ⅲ, intracardiac aneurysm of the septal portion of the tunnel, with or without right ventricular out-flow tract obstruction;and type Ⅳ, a combination of types Ⅱ and Ⅲ.LV ejection fractions (EFs) were assessed using the biplane Simpson method, with manual tracing of digital images.Color Doppler flow imaging (CDFI) was used to indicate the presence of valve regurgitation, aortic stenosis and abnormal communication through the tunnel.The position, shape, and caliber of the tunnels were measured.All patients were regularly followed-up with TTE and/or TEE during hospitalization and after discharge.A histological examination of the tunnel walls was performed in patients undergoing surgery.Data are expressed as the mean ± SD or as percentages.The comparison of the mean diameter of the tunnel measured by echocardiography and surgical results was performed using an independent samples t test.Statistical analysis was performed using commercially available software (JMP 9.0, SAS Institute Inc., Cary, NC, USA), and a P value of< 0.05 was considered to be statistically significant.Results:Clinical presentations Ten patients (7 males and 3 females) were diagnosed with ALVT using TEE.Nine cases were selected in this study, and one patient was excluded because of the intraoperative diagnosis of a right coronary sinus aneurysm rupture into the LV.The mean age of the 9 included patients was 33.8 years (range, 20 to 42 years), with a mean height of 167.56 ± 5.57 cm, a mean weight of 64.44 ± 7.38 kg, and a mean heart rate of 87 ± 14 beats/min.All patients presented with a murmur and were referred to the department of cardiovascular surgery.Chest X-ray films revealed cardiomegaly with left ventricular prominence in eight patients.The ECG showed left ventricular hypertrophy and associated nonspecific ST segment elevation and T wave changes in six patients, complete atrioventricular block and non-paroxysmal ventricular tachycardia in two patients, and normal physiology in one patient.None of the patients had a history of endocarditis.Echocardiographic examinations All 9 patients underwent preoperative or intraoperative 2D and RT-3D TEE.All patients had good quality 2D, CDFI and RT-3D TEE images, with amean LVDD of 56.22 ± 5.07 mm (range, 45 to 61 mm) and an LV mean ejection fraction (EF) of 55.78 ± 7.50% (range, 48 to 71%).In 8 cases, the evident volume overload of the LV was noted.An EF of≤ 55% was present in 6 cases (67%).The 2D and 3D TEE images showed the aortic and ventricular ends of the tunnel and its spatial relationship to the surrounding structures, such as the coronary arteries and the coronary sinuses.The echocardiographic characteristics of the tunnels varied significantly, originating superior to the junction of the left coronary sinus (LCS) and the noncoronary sinus (NCS) in 2 patients, to the right coronary sinus (RCS) in 3 patients, to the commissure of the LCS and the RCS in 3 patients, and to the NCS in 1 patient.The 3D-TEE allowed for an unprecedented "enface view" of the tunnel from the AO, which corresponds to the surgeons view, or alternatively, inferiody from the LV.On the aorto-left ventricular long axis view, 2D TEE imaging showed the entire length of the tunnel, dilation of the aortic valve annulus and the coronary sinus.It also demonstrated the aneurysmally dilated aortic end of the tunnel and its relationship to the coronary artery.The aneurysmal dilatation of the tunnel causes the aortic valve annulus to bulge into the left ventricular outflow tract (LVOT), with resulting distortion of the aortic valve, which was responsible for aortic regurgitation (AR).Prolapse of the impaired aortic valve and orifices of the tunnel in the AO and in the LV were observed.TEE color Doppler flow imaging (CDFI) displayed high velocity turbulent retrograde flow into the LV through both the aortic valve and the tunnel orifices during diastole, in addition to blood filling through the mitral valve.During systole, CDFI displayed the flow from the LV to the aorta through both the aortic valve and the tunnel.The relationship of the tunnel to the coronary artery was also demonstrated.Prolapse of the impaired valve cusps in diastole was observed in four patients.The mean diameter of the tunnel orifices in the LV or the AO measured by echocardiography was 6.2 ± 4.1 mm (range, 1 to 18 mm).A tiny tunnel with a slit-like opening at the aortic end was diagnosed in a 20-year-old girl without aortic valve distortion.AR was absent in 2 patients, mild in 3 patients, moderate in 1 patient and severe in 3 patients, for a total of 7 cases (78%) with AR.Mitral regurgitation (MR) was trivial or absent in 3 three patients, mild in 1 patient and moderate in 5 five patients, for a total of 6 cases (67%) with MR.Seven patients presented with normal coronary arteries, except for one patient, whose coronary involvement was diagnosed by preoperative TEE and confirmed during surgery.A ventdcular septal defect (VSD) was diagnosed in 2 patients.Four patients were confirmed to have decreased ejection fractions, with impaired LV function.Surgery and follow-up After detailed information about the morphology and relations of the tunnel was demonstrated by both 2D and RT-3D TEE, the surgical plans were set, and the operations were successfully performed in eight patients.Artificial mitral valve annuli were implanted in two patients.The caliber of the tunnel in the LV or AO was measured and had an average value of 6.8 ± 3.9 mm (range, 2.2 to 18.4 mm).There was no significant difference between the TEE findings and the surgical results (P > 0.05).All patients were alive at the one-year follow up.Seven patients had uneventful postoperative courses, although one patient underwent reoperation for prosthetic aortic and mitral valve replacement after 4 months due to an infective endocarditis.Unfortunately, 15 months following the second surgery, this patient died of cardiac arrest, with severe paravalvular leakage of the prosthetic aortic valve noted by 2D TEE in preparation for a third surgery.The 20-year-old female patient was instructed to follow-up clinically with serial echocardiograms.Two of the echocardiograms showed trivial residual ALVT, with mild AR.Residual AR was shown in 1 patient at the early (< 6 months postoperatively) follow-up.The other 4 patients have been followed up for 12, 18, 25 and 39 months and are currently asymptomatic, with no apparent increases in the degree of AR assessed via echocardiogram.Pathological and histological sections demonstrated that the segment of the sinotubular ridge closest to the aortic orifice was distorted or displaced by the tunnel.Structurally, it was composed of diffuse fibrous tissue rather than muscle, as in a normal heart.Conclusions: ALVT is a rare cardiac malformation that has good long-term outcomes following early surgery.ALVT and associated lesions can be accurately diagnosed by 2D and RT-3D TEE, which can provide both the necessary morphologic information to enable surgical correction without angiography and serial noninvasive follow-up studies.3D-TEE allows for an unprecedented"enface view" of the tunnel from the AO, which corresponds to the surgeons view, or alternatively, inferiorly from the LV.RT-3D TEE should be regarded as an important adjunct to the standard 2D TEE examination when making decisions for managing patients with ALVT before and during surgery.ALVT should be repaired as soon as the diagnosis is confirmed, unless the defect is small.Early intervention may prevent further LV dilation or damage to the aortic root and valve.Early operation is associated with excellent outcomes, whereas repair at an older age is associated with a high incidence of heart failure and residual AR requiring further surgery.