We thank Dr. Struthers et al. for their interest in our article1and their suggestions for future research based both on high preoperative levels of brain natriuretic peptide (BNP) and the specifics of underlying cardiac pathology.
We are well aware that fully phenotyping, i.e. , identification of the underlying cardiac disease and targeted therapy, comprises current and future possibilities for primary and secondary prevention in the individual cardiologic patient, as recently highlighted by Drs. Struthers and Lang.2
Preoperative phenotyping, however, is often limited by timely constrictions due to concomitant and disabling illness that necessitates a rapid surgical intervention. Furthermore, surgical illness and the specifics of the perioperative period (obesity, immobilization, opioids, anemia, catecholamine surges, and hypercoagulability) may both obscure and aggravate the underlying cardiac disease. In addition, recent trials in patients with stable coronary artery disease demonstrated that knowledge of functional coronary artery stenoses and subsequent prophylactic revascularization did not improve cardiac outcome when compared with optimized conventional therapy.3,4
For many years, anesthesiologists have been relying on clinical risk indices to define perioperative cardiac risk.5Recently BNP, though being an “unspecific” marker of cardiac damage, outperformed risk indices6and stress testing.7In the future, determination of BNP might therefore complement anesthesiologic risk assessment by identifying high-risk/high-BNP patients and define the best time (preoperative, early postoperative, or after surgical rehabilitation) for further cardiac evaluation and targeted therapy. However, because of the lack of well-established cutoffs of BNP,2influence of various patient-specific factors,8and perioperative undulation of BNP, “high” values will have to be defined and validated in future studies in different surgical settings.
*Medical University Graz, Graz, Austria. email@example.com