Abstract
Background
Patients with severe aortic stenosis (AS) and prior cardiac surgery undergoing aortic valve replacement (AVR) are at high risk. Transapical AVR might reduce the risk in patients not suitable for the transfemoral approach. We aimed to describe the fluoroscopy and left anterior descending artery (LAD) angiography guidance technique for transapical AVR access and the initial related procedural results.
Methods
Patients with severe AS and prior cardiac surgery undergoing transapical AVR using LAD angiographic-guided apical puncture were analyzed ( n =9). Additional guidance was added to the standard technique as follows. Minithoracotomy was performed at the level of the intercostal space in closer relationship to the apex identified by fluoroscopy. LAD angiography was performed at the time that the area of interest was recognized by radiopaque marker to ensure puncture lateral to the LAD. Apical needle puncture was performed under fluoroscopy guidance directed towards the aortic root.
Results
The population had a mean age of 83 years and was more frequently male (89%) with a high-risk profile (mean Society of Thoracic Surgeons score of 11%). Two patients received the 23-mm Edwards SAPIEN valve, and seven patients received the 26-mm SAPIEN device. All nine patients underwent successful implantation of transcatheter aortic valves with virtual abolishment of transaortic gradient, without procedural complications.
Conclusion
Fluoroscopy and angiography for guidance of the transapical approach facilitate a safe and rapid access to the apex, insuring no risk of damage to the LAD or to large diagonals.
1
Introduction
Transcatheter aortic valve implantation is an effective and definite therapy to treat high-risk patients with severe aortic stenosis (AS) . Transapical aortic valve replacement (AVR) might reduce the risk of conventional surgical AVR in very high-risk patients who are not suitable for a transfemoral approach . Indeed, operative mortality for conventional surgical AVR in patients with prior coronary artery bypass grafting (CABG) has been reported to be as high as 16% . Of particular interest, the transapical approach might reduce the operative risk for patients with previous cardiac surgery, as surgical trauma and need for bypass circulation are minimized. Nonetheless, previous cardiac operation poses additional strain to the transapical access due to the frequent presence of pericardial adhesions, which makes it more difficult to identify some key surgical structures, such as the apical left anterior descending artery (LAD) . As a result, in patients with prior heart surgery, we adopted the practice of performing a LAD angiogram as guidance for optimal location of the apical puncture and pledged sutures. We describe the fluoroscopy and LAD angiography guidance technique for transapical access and the initial related procedural results in patients with prior cardiac surgery undergoing transapical AVR.
2
Patients and methods
2.1
Study population
Patients with prior cardiac surgery undergoing transapical AVR using LAD angiographic-guided apical puncture performed at our center from September 2010 to April 2011 were analyzed ( n =9). All patients had severe symptomatic AS confirmed by preoperative transthoracic echocardiogram and invasive hemodynamic evaluation. In all cases, the iliofemoral system evaluated by computed tomography (CT) angiogram was not suitable for transfemoral approach. The Society of Thoracic Surgeons (STS) score and the logistic European System for Cardiac Operative Risk Evaluation (EuroSCORE) were calculated for all patients. All patients gave written consent for the transapical AVR procedure, and the study was conducted under local Institutional Review Board approval.
2.2
Transapical access angiographic-guided technique
The procedures were performed by a dedicated team of cardiothoracic surgeons and interventional cardiologists in a hybrid catheterization laboratory in a completely sterile environment under fluoroscopy/angiographic imaging of a monoplane Philips AlluraXper FD20 system (Philips Healthcare, Netherlands). The procedure was performed with the patient intubated under general anesthesia provided by a cardiovascular anesthesiologist. The procedure was continuously monitored by transesophageal echocardiogram (TEE) performed by an experienced echocardiographer. A perfusionist and a heart–lung machine were present in the room.
After percutaneous transitory right ventricle pace wire placement, a left anterior minithoracotomy was performed at the level of the intercostal space in closer relationship to the apex identified by fluoroscopy guidance ( Fig. 1 ). Careful examination of preoperative chest CT scan to evaluate the relationship of the apex and the chest wall was performed to also assist in the positioning of the incision. The surgical technique was based on procedures described by Walther et al. . After careful dissection of the pericardium and appropriate apical exposure, the LAD was injected from the native left main coronary artery or grafted conduit. At the same time, the apical area of interest was recognized by radiopaque marker (needle/hemostat) to ensure a puncture site lateral to the LAD ( Fig. 2 ). After selecting the correct puncture site, two apical purse-string sutures were placed deep into the myocardium, but did not penetrate the ventricle cavity.
2.3
Fluoroscopy-guided apical puncture, sheath insertion and valve implantation
A 5-Fr pigtail catheter was placed in the aortic root from the femoral access, and optimal projection for valve deployment (angle allowing for separate aligned view of three sinuses) was identified by rotational aortogram (typically performed with 10° of caudal angulation). The defined apical area was punctured at the center of the purse-string sutures with an 18-gauge needle directed towards the aortic root fluoroscopically guided by the pigtail catheter ( Fig. 3 ). Heparin was administered at 100 U/kg to achieve an activated clotting time >300 s after pericardiotomy. A soft J-guidewire was inserted antegrade across the aortic valve, which was positioned in the descending aorta. It is necessary to ensure that the guidewire has not engaged the mitral valve apparatus prior to crossing the aortic valve. Subsequently, a stiff guidewire (Amplatz super stiff, 260 cm) was positioned into the descending aorta using a 5-Fr Judkins right 4 catheter.
The 26-Fr transapical sheath (Ascendra delivery system, Edwards Lifesciences, Irvine, CA, USA) was consequently inserted positioned 4–5 cm below the aortic valve as visualized under fluoroscopy. Balloon-expandable transcatheter stent-prosthesis xenograft valves of 23- or 26-mm diameter (Edwards SAPIEN THV, Edwards Lifesciences) were used according to the diameter of the aortic valve annulus measured by TEE. A 23-mm valve was used for annulus sizes <22 mm, and a 26-mm valve was used for annulus sizes >22 mm. Valve positioning and implantation were performed following standardized technique based on prior description by Walther et al. .
2.4
Statistical analysis
Continuous variables are presented as mean ± S.D., and categorical variables are presented as percentages.
2
Patients and methods
2.1
Study population
Patients with prior cardiac surgery undergoing transapical AVR using LAD angiographic-guided apical puncture performed at our center from September 2010 to April 2011 were analyzed ( n =9). All patients had severe symptomatic AS confirmed by preoperative transthoracic echocardiogram and invasive hemodynamic evaluation. In all cases, the iliofemoral system evaluated by computed tomography (CT) angiogram was not suitable for transfemoral approach. The Society of Thoracic Surgeons (STS) score and the logistic European System for Cardiac Operative Risk Evaluation (EuroSCORE) were calculated for all patients. All patients gave written consent for the transapical AVR procedure, and the study was conducted under local Institutional Review Board approval.
2.2
Transapical access angiographic-guided technique
The procedures were performed by a dedicated team of cardiothoracic surgeons and interventional cardiologists in a hybrid catheterization laboratory in a completely sterile environment under fluoroscopy/angiographic imaging of a monoplane Philips AlluraXper FD20 system (Philips Healthcare, Netherlands). The procedure was performed with the patient intubated under general anesthesia provided by a cardiovascular anesthesiologist. The procedure was continuously monitored by transesophageal echocardiogram (TEE) performed by an experienced echocardiographer. A perfusionist and a heart–lung machine were present in the room.
After percutaneous transitory right ventricle pace wire placement, a left anterior minithoracotomy was performed at the level of the intercostal space in closer relationship to the apex identified by fluoroscopy guidance ( Fig. 1 ). Careful examination of preoperative chest CT scan to evaluate the relationship of the apex and the chest wall was performed to also assist in the positioning of the incision. The surgical technique was based on procedures described by Walther et al. . After careful dissection of the pericardium and appropriate apical exposure, the LAD was injected from the native left main coronary artery or grafted conduit. At the same time, the apical area of interest was recognized by radiopaque marker (needle/hemostat) to ensure a puncture site lateral to the LAD ( Fig. 2 ). After selecting the correct puncture site, two apical purse-string sutures were placed deep into the myocardium, but did not penetrate the ventricle cavity.
