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Paper text:
following the popularization of beating heart techniques for myocardial revascularization , its use for heart valve surgery has proven its safety in the second half of 2000s and successful results have been reported .
various protocols have been defined for myocardial protection during arrested heart surgery , but each strategy has its limitations and pitfalls and none has proven ideal .
particularly , in patients with compromised ventricular functions , cardioplegic arrest may make weaning from cardiopulmonary bypass ( cpb ) very challenging .
the on - pump beating heart technique without aortic cross - clamping is an acceptable alternative to mitral valve surgery with low operative morbidity and mortality in cases with compromised ventricular functions .
mitral valve replacement surgery was successfully performed via right thoracotomy under cpb without aortic cross - clamping .
a 64-year - old man was admitted to our hospital with the complaints of severe dyspnea , orthopnea , and palpitations .
he had received an implantable cardioverter - defibrillator two years previously and had been followed up for mitral regurgitation and atrial fibrillation with medical therapy for 4 years .
echocardiography documented third - degree mitral regurgitation and first - to - second - degree tricuspid regurgitation .
the left ventricular end - diastolic diameter was 8.0 cm , left ventricular end - systolic diameter was 6.4 cm , left atrial diameter was 54 mm , and the calculated systolic pulmonary artery pressure was 52 mmhg .
normothermic cpb ( 3637 c ) was established following femoral arterial and selective bicaval venous cannulation with a flow rate of 2.2 l / min / m .
the aorta was not cross - clamped , no cardioplegia was used during the procedure , and the heart was allowed to beat .
the patient was kept in the trendelenburg position throughout the procedure while the aortic root was vented in order to prevent any possible air embolism .
the patient was intubated for 12 hours , kept in the intensive care unit for 48 hours , and discharged on the sixth postoperative day .
beating heart mitral valve surgery has the particular advantage of minimizing ischemia - reperfusion injury due to aortic cross - clamping and myocardial ischemia . during the global myocardial ischemic period , especially in the previously damaged myocardium with a predisposition , due to increased demand and reduced perfusion
physiologic normothermic blood perfusion of the heart is employed during the procedure , which protects the myocardium .
although the adverse events related to cpb itself can not be avoided , the avoidance of myocardial damage makes the beating heart technique a logical alternative for patients with poor ventricular functions . regarding the blood transfusion requirements ,
one of the most feared complications of beating heart mitral valve surgery is air embolism .
the position of the patient ( head down ) , continuous aortic root venting , strict employment of routine de - airing maneuvers , intraoperative use of transesophageal echocardiography for the detection of bubbles , and most importantly a competent aortic valve decrease the incidence of air embolism .
we believe that aortic cross - clamping causes micro and macro emboli from the aorta as cicekoglu et al . suggested .
furthermore , it has been documented that beating heart mitral valve surgery has no adverse effects on neurocognitive functions . beating heart mitral valve surgery
has a major drawback : the presence of aortic insufficiency . in case of aortic insufficiency
, the blood may flood to the operation field and render exposure very challenging . as a matter of fact
, the concept of the beating heart technique has a limited surgical exposure , so there is a limited potential for complex mitral valve procedures .
the presence of aortic competence maintains a bloodless field , but still this approach causes a relatively blood - filled field compared to conventional mitral valve surgery .
in addition to this , aortic competence also serves as a secure aortic - clamp and prevents air embolism .
our patient had dilated cardiomyopathy with a left ventricular end - diastolic diameter of 8.0 cm .
the use of cardioplegic arrest may further compromise ventricular functions , tipping the balance in favor of beating heart surgery .
our patient 's cardiomyopathy prompted us to protect all his chordae ; we , therefore , did not perform leaflet resection and sutured the bioprosthesis to the annulus .
we opted against ring annuloplasty because tethering would not lead to a satisfactory reduction in the annular size and would give rise to residual insufficiency .
we believe that beating heart mitral valve surgery can be safely performed with all precautions taken to prevent the most feared complication : the air embolism .
not cross - clamping the aorta may provide further protection since the aorta is not manipulated .
the procedure should be carefully planned and practiced mentally by the whole team prior to the operation because all the steps are somewhat different to routine cardiovascular surgical practice .
abstractglobal myocardial ischemia and ischemia - reperfusion injury are potential adverse events related with cardioplegic arrest . beating heart surgery has avoided such complications and adapted to valve surgery following successful results published on myocardial revascularization . 
 difficulty in weaning from cardiopulmonary bypass may be lessened by using on - pump beating heart surgery for mitral valve interventions . 
 here we describe a 64-year - old male patient with severe mitral regurgitation and dilated cardiomyopathy . beating heart mitral valve replacement surgery 
 was performed without aortic cross - clamping through a right thoracotomy approach . 
 we believe that , particularly in patients with poor left ventricular functions , beating heart mitral valve surgery may be advantageous .