AORTIC-LEFT VENTRICULAR TUNNEL

BASICS –CONNECTION BETWEEN AORTA AND LV, NOT INVOLVING THE AORTIC VALVE –USUALLY ARISE FROM R CORONARY SINUS, MOST COMMONLY ABOVE THE R CA OSTIUM –COURSES ALONG IV SEPTUM ALONG POST WALL OF RVOT –ENTER LV BELOW VALVE LEAFLETS

EPIDEMIOLOGY 0.001%- 0.11% CONGENITAL HEART DISEASE SLIGHT MALE PREDOMINANCE

ETIOLOGY LIKELY CONGENITAL ? ANOMALOUS VESSEL (ENDOTHELIUM) ? DEFECTIVE INCORPORATION OF DISTAL BULBOUS CORDIS ? SEPARATION OF AORTIC ANNULUS ? MPS DEPOSITION, RESULTS IN DISSECTION ? RUPTURE SINUS OF VALSALVA ANEURYSM

CLASSIFICATION SYSTEM TYPE I –Slitlike orifice of aortic portion –No resultant aortic valve changes TYPE II –Aneurysm of aortic portion of tunnel (extracardiac) +/- resultant valve changes TYPE III –Aneurysm of septal portion (intracardiac) +/- RVOT obstruction TYPE IV –II and III

COMPLICATIONS RESULT IN AI TYPES III AND IV (INTRACARDIAC ANEURYSM) CAN RESULT IN RVOT OBSTRUCTION RARELY, CORONARY ARTERY ORIGINATES WITHIN THE TUNNEL (SURG IMPLICATIONS)

Clinical presentation CHF as infant –Systole- antegrade flow –Diastole- retrograde flow –Results in LV failure, ascending aorta dilatation / aneurysm Symptoms of Aortic Regurgitation - Low diastolic BP -Wide pulse pressure, bounding pulses -Dilated LV -murmur

Associated abnormalities (45%) –Usually aortic valve and coronary arteries –Aortic insufficiency –Aortic valve stenosis –Aortic valve atresia –Bicuspid aortic valve –PDA –ASD and VSD –Absent R coronary artery –Sinus of valsalva aneurysm –IV septum aneurysm

Imaging findings CXR Cardiomegaly Dilated ascending aorta

DIAGNOSIS ECHO w/ Doppler -differentiate between A-LV tunnel and AI -Key- different outcomes for tunnel repair vs AR repair or aortic valve replacement (much better prognosis for tunnel repair) - w/ a tunnel, don’t see retrograde flow via the aortic valve - High index of suspicion if see sig AI in infant

Diastolic flow via tunnel Martins, et al. Aortico-left ventricular tunnel: 35 year experience. JACC 2004; 44:

diagnosis Most definitive- cardiac cath –Can do temp balloon occlusion to discern AR through the valve vs flow via tunnel A= tunnel B=asc aorta C=R CA

DIAGNOSIS Limited experience with MRI Overall- need to eval for coronary ostia location, RVOT obstruction

Disease Course w/o surgery, usually results in CHF, sudden death (100%) –Rare exception of very small tunnel can survive in infancy with medical mgmt –1 study of 11 patients over 35 years (Boston)- 1 pt had spont closure of tunnel (had been misdiagnosed as AR rather than a tunnel, and so underwent valvuloplasty)

surgery Goal- preserve coronary arteries, conduction system, aortic valve If slit like tunnel (type I)- could use suture or closure of aortic root –Can later have dehiscence

Preferred surgical technique Patch both proximal and distal portions with pericardium, Gore-Tex, or Teflon (as long as its placement won’t impact the aortic valve structurally) May need to reimplant coronary artery 11-20% surg mortality

Post-op Complications Suture failure Aortic regurgitation (even years later), may need repeat surgery –Increased risk if surgery done at later age

Long term Thought that half of patients may still need valve replacement at some point

References Allen, et al. Moss and Adams’ Heart Disease in Infants, Children, and Adolescents. Section 32- Congenital anomalies of the coronary vessels and the aortic root. Grab, et al. Prenatal diagnosis of an aortico-left ventricular tunnel. Ultrasound in Obstetrics and Gynecology : Hsu, et al. Virtual intraluminal evaluation of aortico-left ventricular tunnel by multislice computed tomography. International Journal of Cardiology : Mavroudis and Backer. Pediatric Cardiac Surgery. 3 rd edition Martins, et al. Aortico-left ventricular tunnel: 35 year experience. JACC. 2004; 44: Mitropoulos, et al. Aorto-left ventricular tunnel: An alternative surgical approach. The Annals of Thoracic Surgery. 2006; 82: