The "Ice Age" in Cardiac Surgery: Evolution of the "Siberian" Method of Brain Protection During Deep Hypothermic Perfusionless Circulatory Arrest.

Deep hypothermic perfusionless circulatory arrest was the first practical neuroprotective technique used for open-heart surgery. It was refined at the Novosibirsk Medical Research Center in Siberia and was actively used from the mid-1950s until 2001.This review describes the development of this technique and its contribution to our understanding of the dynamic changes in human physiology during induced hypothermia for circulatory arrest without extracorporeal perfusion. Deep hypothermic perfusionless circulatory arrest was an important stepping stone in the development of modern approaches in neuroprotection and monitoring during cardiac surgery.

Stroke After Transcatheter Aortic Valve Replacement: Incidence, Definitions, Etiologies and Management Options.

Neurologic complications after transcatheter aortic valve replacement are devastating. The etiologies of stroke in this setting are best addressed in an integrated fashion during each phase of the perioperative pathway. The conduct of this triphasic approach will continue to be refined to reduce the stroke risks even further, given the major focus on aspects such as embolic protection devices and valve thrombosis. This neurologic focus in transcatheter aortic valve replacement has transformed the investigational approach to neurologic events in cardiovascular clinical trials, resulting in novel guidelines for the diagnosis and assessment of neurologic injury after cardiovascular interventions.

Aortic Regurgitation in Acute Type-A Aortic Dissection: A Clinical Classification for the Perioperative Echocardiographer in the Era of the Functional Aortic Annulus.

The functional aortic annulus offers a clinical approach for the perioperative echocardiographer to classify the mechanisms of aortic regurgitation in acute type-A dissection. Comprehensive examination of the functional aortic annulus in this setting using transesophageal echocardiography can guide surgical therapy for the aortic root by considering the following important aspects: severity and mechanism of aortic regurgitation, extent of root dissection, and the pattern of coronary artery involvement. The final choice of surgical therapy also should take into account factors, such as patient presentation and surgical experience, to limit mortality and morbidity from this challenging acute aortic syndrome. This review explores these concepts in detail within the framework of the functional aortic annulus, detailed anatomic considerations, and the latest literature.

The functional aortic annulus in the 3D era: focus on transcatheter aortic valve replacement for the perioperative echocardiographer.

The functional aortic annulus represents a sound clinical framework for understanding the components of the aortic root complex. Recent three-dimensional imaging analysis has demonstrated that the aortic annulus frequently is elliptical rather than circular. Comprehensive three-dimensional quantification of this aortic annular geometry by transesophageal echocardiography and/or multidetector computed tomography is essential to guide precise prosthesis sizing in transcatheter aortic valve replacement to minimize paravalvular leak for optimal clinical outcome. Furthermore, three-dimensional transesophageal echocardiography accurately can quantify additional parameters of the functional aortic annulus such as coronary height for complete sizing profiles for all valve types in transcatheter aortic valve replacement. Although it is maturing rapidly as a clinical imaging modality, its role in transcatheter aortic valve replacement is seen best as complementary to multidetector computed tomography in a multidisciplinary heart team model.

New frontiers in aortic therapy: focus on current trials and devices in transcatheter aortic valve replacement.

The first decade of clinical experience with transcatheter aortic valve replacement since 2002 saw the development of 2 main valve systems, namely the Edwards Sapien balloon-expandable valve series and the Medtronic self-expanding CoreValve. These 2 valve platforms now have achieved commercial approval and application worldwide in patients with severe aortic stenosis whose perioperative risk for surgical intervention is high or extreme. In the second decade of transcatheter aortic valve replacement, clinical experience and refinements in valve design have resulted in clinical drift towards lower patient risk cohorts. There are currently 2 major trials, PARTNER II and SURTAVI, that are both evaluating the role of transcatheter aortic valve replacement in intermediate-risk patient cohorts. The results from these landmark trials may usher in a new clinical paradigm for transcatheter aortic valve replacement in its second decade.