Terapia chirurgica delle Valvulopatie Trattamento chirurgico della valvulopatia aortica

Aortic valve excision.

Mechanical prosthesis implantation.

Bioprosthesis Implantation

(a) Preoperative angiogram without opacification (a) Preoperative angiogram without opacification. The heavily calcified aortic root and aortic cusps are seen (triangles). (b) Preoperative aortogram. The stenotic sinotubular ridge (17 mm in diameter; arrow) and the stenotic aortic annulus (17 mm) are seen. The second degree of aortic regurgitation is also observed. (c, d) Postoperative aortograms: The enlar-ged sinotubular ridge and aortic annulus asso-ciated with the inserted 19-mm CarboMedics valve are seen. The pros-thesis placed almost pa-rallel to the original aor-tic annulus shows a nor-mal motion with minimal central regurgitation

Size of Prosthesis for AVR a) 19 mm · Prohibitively high LV/Ao gradient · Enlarge the aortic root or perform Ross procedure instead b) 21 mm · Adequate size if BSA 1.5-1.7 M2 and patient is sedentary · If BSA greater than 1.7 M2 = enlarge the aortic root (10 year survival 80% vs 60%) c) 23 mm or larger · Acceptable LV/Ao gradient in all patients

Risk Factors for Survival after AVR · Advanced age · Functional status (NHYA class) · Depressed LV function (aortic incompetence) · Coronary artery disease · Presence of endocarditis · Aneurysm of ascending aorta · Mismatch of prosthesis and body size

Survival After AVR a) Early (hospital) death - 3-6% b) Time-related survival · 5 years - 75% · 10 years - 60% · 15 years - 40% c) Mode of death · Early due to CHF, hemorrhage, infection, CVA · Sudden - 20% · Device related - 20%

Stentless Bioprosthesis Sorin Pericarbon The CryoLife-O'Brien porcine stentless aortic valve.

In patients with significant aortic valve disease conventional (stented) aortic valve replacement is the standard approach Implantation of a stentless aortic valve (SAV) is technically more demanding However SAV may offer better hemodynamic function and improved left ventricular reverse remodeling

postoperative bloodflow Conventional Stentless

Mean gradient at rest and maximal exercise Peak gradient at rest and maximal exercise. The change in gradient from rest to exercise is compared with the change in the normal group. *p < 0.001 versus NOR. (NOR = normal native aortic valves; TSPV = Toronto stentless porcine valve; FR = Medtronic Freestyle; SOR = Sorin Bicarbon; SJM = St. Jude Medical.) S.Silberman: Exercise hemodynamics of aortic prostheses: comparison between stentless bioprostheses and mechanical valves Ann. Thorac. Surg. 2001;72:1217-1221 Mean gradient at rest and maximal exercise

LVH is an independent cardiac risk factor "An increase in left ventricular mass predicts a higher incidence of clinical events, including death, attributable to cardiovascular disease. " Levy et al, N Engl J Med 1990;322:1561

LV mass - index [g/m2] Indexed ventricular mass regression in both groups over time. (CE = Carpentier-Edwards stented valve; LVMI = left ventricular mass index; SPV = Toronto stentless porcine valve.). G. Cohen et al. Are stentless valves hemodynamically superior to stented valves? A prospective randomized trial Ann. Thorac. Surg. 2002;73:767-778.

Actuarial survival between stented and stentless groups Actuarial freedom from reoperations between the stented and stentless groups. Actuarial survival between stented and stentless groups M. Vrandecic et al. Retrospective clinical analysis of stented vs. stentless porcine aortic bioprostheses Eur. J. Cardiothorac. Surg. 2000;18:46-53.

Aortic Homograft

Homograft inplantation: the “root” technique

Operative mortality for aortic Homograft insertion

Left ventricular mass index (LVMI) preoperatively (PREOP) and 8 months after (POSTOP) aortic valve replacement. The homograft and stentless valves expressed the maximum LVMI reduction. This is evident in all cases (A) and in patients with a preoperative LVMI of 180 g/m2 or less (B). In patients with a preoperative LVMI of 180 g/m2 or more (C) the homograft treatment achieved the best results. (I = intact; H = homografts; T = Toronto; F = freestyle; C = controls). Ann. Thorac. Surg. 1999;67:966-971. Left ventricular mass reduction after aortic valve replacement: homografts, stentless and stented valves Daniele Maselli

Long-term survival after Homograft aortic valve replacement

Cumulative survival rates after homovital homograft aortic valve replacement with root replacement, freehand two-suture line technique (subcoronary), or either technique with associated procedures.

Cumulative survival rates of all patients undergoing homovital homograft aortic valve replacement, including early death. Numbers above the abscissa indicate patients at risk at 1, 5, and 10 years. Five- and 10-year survival rates plus or minus SEM are given

A depiction of the interrelationships between the overlapping mechanisms of allograft valve failure influenced by known risk factors—(younger) recipient age, (older) donor age, (larger) aortic root diameter, insertion technique, and valve preservation technique. Although compiled from a series of cryopreserved and antibiotic sterilized valves, these risk factors may play a role in failure of either type of valve.

Pulmonary Autograft (Ross Procedure- 1967) Advantages Viable tissue, excellent hemodynamics Near 0% thromboembolism, growth potential Non-antigenic Pulmonary valve equal in strength as aortic valve Disadvantage Creating 2-way valve pathology from single valve disease Results Freedom from re-operation 81% at 8 years 5-10% annular dilatation and regurgitation Pulmonary homograft deterioration Technique Root replacement preferred Tailoring of aortic/pulmonary size mismatch Bolstering ring with Dacron strip Long-term follow-up still accruing

The Ross Operation

Operative mortality for aortic valve replacement with pulmonary autograft

Reparative aortic valve surgery. Reproduced from Duran and colleagues

The Marfan syndrome The most common genetically determined disorder affecting adults (1/10,000 births). It is associated with a defect on chromosome 15 that affects fibrillin synthesis. (Fibrillin and elastin represent the major components of the elastic fiber system). Histopathologically, the aorta demonstrates cystic medial degeneration: disruption of elastic fibers fibrosis of the media. The abnormal elastic tissue predisposes patients to aortic root dilation with or without associated aortic regurgitation (75-85%), significant mitral regurgitation (30%). In addition to cardiovascular disease, the Marfan syndrome is associated with ocular, pulmonary, musculoskeletal, and central nervous system abnormalities

Natural History The average age of death is approximately 32 years. The majority of deaths are cardiovascular: related to aortic root dilation in 60–80%: Aortic rupture dissection, heart failure from valvular disease (Aortic and mitral) The mean rate of aortic root dilation is 1.9 mm/year (however, individual rates of aortic expansion are highly variable and unpredictable). Acute dissection may occur in ascending aortas that are not greatly dilated. The risk of aortic root complications may be higher in individuals with a family history of aortic dissection.

The Marfan Syndrome

Surgical Procedures “Valve-Sparing Operation” (M. Yacoub – T. David) COMPOSITE GRAFT Replacement of the ascending aorta and aortic valve with a composite graft containing a mechanical valve and a collagen- or gelatin-impregnated Dacron graft and reimplan-tation of the coronary arteries . AORTIC HOMOGRAFT Aortic root allografts can be used to replace the aortic valve, the aortic sinuses, and the ascending aorta. PULMONARY AUTOGRAFTS Pulmonary root autografts are also used to replace the aortic root and adjacent ascending aorta. “Valve-Sparing Operation” (M. Yacoub – T. David) In cases of annuloaortic ectasia and aortic leaflets are normal, annuloplasty can be performed by suturing an appropriately sized Dacron tube graft circumferentially to the tissue immediately beneath the aortic annulus. The dilated aortic sinuses are excised, the aortic valve is resuspended within the tube graft, and the coronary arteries are reimplanted. The advantages: the avoidance of anticoagulation and lower risk of thromboembolism and endocarditis

DILATAZIONE DELL’AORTA ASCENDENTE definizione della patologia ⇧Diametro > 1,5 x Diametro predetto Diametro predetto Età Superficie corporea Rilevanza della comorbidità Connettivopatie Aorta bicuspide

Scopi dell’intervento Correzione dell’insufficienza aortica Protesi meccanica Protesi biologica Homograft/Autograft Chirurgia conservativa Eliminare rischio di rottura/dissezione

Dilatazione aorta ascendente indicazioni al trattamento Criteri di indicazione Cut-off standard 50 mm (no aorta bicuspide, no connettivopatie) Velocità di accrescimento della dilatazione Necessità di almeno 2 misurazioni distanti ≥ 2mm/anno Rischio personalizzato BSA, età, comorbidità, familiarità R= eC(MD-PD)/MD

Indicazioni Chirurgiche specifiche nella sindrome di Marfan Diametro della radice aortica ≥  45mm Anamnesi familiare positiva per dissezione e diametro della radice ≥  40 mm Rischio personalizzato

Dissezione aortica Evoluzione a insufficienza aortica, rottura, sindrome coronarica acuta, sindrome ischemica neurologica, splancnica o periferica M/F 3:1 Ipertensione 70 - 90%; connettivopatie; valvola aortica bicuspide; coartazione aortica

la chirurgia della radice aortica La terapia chirurgica è il solo trattamento definitivo della patologia della radice aortica la chirurgia della radice aortica (sostituzione valvolare e/o dell’aorta ascendente) rappresenta circa il 15% degli interventi cardiochirurgici dell’adulto

Intervento di Bentall Sostituzione della valvola aortica e dell’aorta ascendente con reimpianto delle coronarie

Intervento di ROSS

SOSTITUZIONE PROTESICA DELLA RADICE AORTICA                                                                                    

Crescente impulso allo sviluppo di tecniche conservative: Assenza di un sostituto “ideale” che possa riprodurre la “perfezione” della radice aortica nativa normale La scelta della strategia chirurgica ha l’obiettivo di offrire al paziente i migliori vantaggi clinici e funzionali Crescente impulso allo sviluppo di tecniche conservative: “Sparing Technique”

“Sparing technique” anche in presenza di alterazione valvolare: PRESERVARE la “Radice Aortica” come entità anatomo-funzionale “Sparing technique” anche in presenza di alterazione valvolare: Endocardite Valvola bicuspide - Prolasso di una o più cuspidi

LA VALUTAZIONE ECOGRAFICA: TEE Misura di annulus, giunzione S-T e dei seni Valutazione anatomofunzionale della valvola

Classificazione funzionale dell’IAo e della patologia della radice Functional type Lesions Type 1: normal cusp motion 1a: sino-tubular junction dilation 1b: ST junction + sinuses dilation 1c: annular dilation 1d: cuspal defect Type 2: cusp prolapse Excess of cuspal tissue Commissure flaided or distorted Type 3: restricted cusp motion Fibrous thickening Calcification

Type 1a Sino-tubular dilation

Type 1b: ST junction + sinuses dilation Aortic remodelling YACOUB DAVID

Tecnica di Yacoub SPARING TECHNIQUE La dilatazione della radice compresi i seni viene escissa. Impianto di protesi retta modellata sulla base di impianto dei lembi valvolari

ST junction + sinuses dilation + annular dilation Type 1b + 1c Aortic root reimplantation “David”

Aortic root reimplantation

Aortic root reimplantation

Aortic root reimplantation Pre-op Post-op

The “pseudosinus model remodelling” SPARING TECHNIQUE The “pseudosinus model remodelling” La dilatazione della radice compresi i seni viene escissa. Impianto di protesi “scalloped” che permette una dinamica tipo seni di Valsalva

Type 1c : annular dilation

Type 1d : cuspal defect LEAFLET EXTENSION

Type 2 : cusp prolapse

Bicuspid valve and STJ dilation

Type 3: restricted cusp motion > commissurorraphy Type 1d + 2 : cuspal defect and prolapse > leaflet repair and free edge reinforcement

SPARING TECHNIQUE Recurrence of Aortic Insufficiency After Aortic Root Remodeling With Valve Preservation Ann Thorac Surg 1999;67:1849 –52)© 1999 by The Society of Thoracic Surgeons

aortic root remodelling SPARING TECHNIQUE Recurrence of aortic insufficiency after aortic root remodelling with valve preservation Ann Thorac Surg 1999;67:1849 –52)© 1999 by The Society of Thoracic Surgeons

SPARING TECHNIQUE

SPARING TECHNIQUE

SPARING TECHNIQUE

SPARING TECHNIQUE

durata e sopravvivenza L’approccio conservativo “sparing technique” nella patologia della radice aortica e/o aorta ascendente rappresenta un’alternativa sicura ed efficace alle tecniche tradizionali dimostrando buoni risultati in termini di durata e sopravvivenza a distanza