Transapical transcatheter aortic valve implantation (TA-TAVI) is increasingly used to treat aortic valve stenosis in high-risk patients. Mixed venous oxygen saturation (SvO(2)) is still the 'gold standard' for the determination of the systemic oxygen delivery to consumption ratio in cardiac surgery patients. Recent data suggest that regional cerebral oxygen saturation (rScO(2)) determined by near-infrared spectroscopy is closely related to SvO(2). The present study compares rScO(2) and SvO(2) in patients undergoing TA-TAVI. n = 20 cardiac surgery patients scheduled for TA-TAVI were enrolled in this prospective observational study. SvO(2) and rScO(2) were determined at predefined time points during the procedure. Correlation and Bland-Altman analysis of the complete data set showed a correlation coefficient of r(2 )= 0.7 between rScO(2) and SvO(2) (P < 0.0001), a mean difference (bias) of 5.8 with limits of agreement (1.96 SD) of -6.8 to 18.3% and a percentage error of 17.5%. At all predefined time points correlation was moderate (r(2 )= 0.50) to close (r = 0.84), and the percentage error was <24%. RScO(2) determined by near-infrared spectroscopy is correlated to SvO(2) during varying haemodynamic conditions in patients undergoing TA-TAVI. This suggests that rScO(2) is reflective not only of the cerebral, but also of the systemic oxygen balance.

In this small patient cohort, intramyocardial CD 133+ cell injection combined with transmyocardial laser revascularization led to an improvement in clinical symptomatology in all patients and in left ventricular function in 4 out of 5 patients, with an unclear effect on myocardial perfusion. Caution is advised when employing this therapy in patients with severely depressed left ventricular function.

Mixed venous oxygen saturation (SvO(2)) is an accepted surrogate parameter for the ratio between oxygen delivery and demand and may thus be used to determine the adequacy of the function of the cardiopulmonary system. Cerebral oxygen saturation monitoring by near infrared spectroscopy is a non-invasive method for the determination of the cerebral oxygen delivery to demand ratio that is applicable outside the operating room or the intensive care unit and does not require calibration. The present case highlights the agreement of non-invasive cerebral and SvO(2) in an 87-year-old female cardiac surgery patient with severe aortic stenosis scheduled for transapical aortic valve replacement during prolonged cardiopulmonary resuscitation.

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TAVI without mechanical circulatory support appears feasible, safe and effective in patients with severe aortic stenosis and severe LVD, but short- and long-term mortality remain high. TAVI should be considered a viable treatment option in this subset of extremely compromised patients.