Kaushal K. Tiwari

Age-dependent changes in elastic properties of thoracic aorta evaluated by magnetic resonance in normal subjects

OBJECTIVES Aortic stiffness is an independent cardiovascular risk factor. Cardiac magnetic resonance (CMR) allows evaluation of aortic elastic properties by different indexes such as distensibility, the maximum rate of systolic distension (MRSD) and pulse wave velocity (PWV). We sought to define age-dependent changes of indexes of elastic properties of the thoracic aorta in healthy subjects. METHODS We enrolled 85 healthy subjects (53 males) free of overt cardiovascular disease subdivided into 6 classes of age (from 15 to >60 years). Distensibility, MRSD and PWV were measured by the analysis of CMR images acquired using a 1.5 T clinical scanner. RESULTS MRSD and distensibility decreased progressively through the classes of age (P < 0.001) after an initial plateau between 20 and 30 years in males and 15 and 20 years in females. Pulse wave velocity increased progressively with the age (P < 0.001). Distensibility was related to body mass index (P = 0.002), surface area (P < 0.005), weight (P = 0.005) and to left ventricular parameters such as mass index (P < 0.001) and end-diastolic volume index (P = 0.002). MRSD was related to end-diastolic volume index (P < 0.001) but not to body parameters. PWV was not related to body and ventricular parameters. CONCLUSIONS This study confirmed that physiological ageing is associated with a progressive impairment of the elastic properties of the aortic wall. Results of this study may be useful for the early identification of subjects with impaired aortic wall properties providing referral values of elasticity indexes assessed by CMR in different classes of age.

eComment: Rationalizing the use of assisted venous drainage during minimally invasive valve surgery

Nomenclature Historical Pages-1.80 m , AVD is unlikely to be required, and, therefore, 2 should not be routinely included in the CPB circuit unless required intraoperatively. This rationale would also have cost-saving implications. Our study also suffers a number of limitations. First, despite all data being prospectively recorded, it has been analysed retrospectively. Second, the patients were not randomised into either of the two groups. Third, the decision to use AVD was purely at the discretion of the surgeon and the clinical perfusionist, based on their assessment of the venous drainage, and thus a selection bias could exist. Finally, it is a relatively small study. Despite these limitations, we have observed that AVD is not essential in every patient who undergoes mAVR, and is more likely to be used in patients with a larger BSA. Partial upper re-sternotomy for aortic valve replacement or re-replacement after previous cardiac surgery. w4x Wang S, Undar A. Vacuum-assisted venous drainage and gaseous microemboli in cardiopulmonary bypass. Limitations using the vacuum-assisted venous drainage technique during cardiopulmonary bypass procedures. drainage method for cardiopulmonary bypass in single-access minimally invasive cardiac surgery: siphon and vacuum-assisted drainage. Vacuum-assisted venous drainage in single-access minimally invasive cardiac surgery. w9x DuBois D, DuBois EF. A formula to estimate the approximate surface area if height and weight be known. Vacuum-assisted venous drainage in extrathoracic cardiopulmonary bypass management during minimally invasive cardiac surgery. Relative importance of venous and arterial resistance in controlling venous return and cardiac output. During minimally invasive valve surgery, a good exposure with a bloodless field is a prerequisite for the ease and success of the surgery. We would like to comment on the issue regarding the use of assisted venous drainage (AVD) raised by the authors w1x. AVD is an important tool available for cardiac surgeons to achieve a bloodless operating field and to empty the heart in order to perform the most important part of the valve surgery. Using direct cannulation of the right atrium might cause crowding of the operative field due to the presence of aortic, venous and venting cannulas as well as aortic-clamp and CO 2 line supply passing through the incision site. Additionally, due to the higher position of the venous cannula in the right atrium, it might need more negative pressure for AVD. Instead, cannulating the femoral vein with double-staged venous cannula (the Remote Access Perfusion Femoral Venousீ cannula, RAP FV; Estech Inc, USA) …

Multiple recurrent periprosthetic leak after a mitral valve replacement in a 30-year-old man.

Partial detachment of intracardiac prosthesis is a common reality in cardiac surgical practice. Its identification and surgical correction can be very crucial for a patient, as well as for the surgeon. In this paper, we report a case of a 30-year-old man with partial detachment of mechanical mitral valve prosthesis. He recently underwent his seventh heart surgery procedure; five of them were caused by recurrent dehiscence of mitral valve prosthesis.

eComment: Does coma state really stop from operating type A aortic dissection patients?

Nomenclature Historical Pages cardiogram, suggesting coronary ostial involvement, were also observed. Echocardiography documented severe aortic regurgitation. Emergency root replacement with a valved conduit was performed with open distal repair at 24 8C, employing selective antegrade cerebral perfusion. Cardiopulmonary bypass, cardioplegic arrest and antegrade cerebral perfu-sion times were 293, 141, and 22 min. The patient was weaned from extracorporeal perfusion with a 0.04 mgykgy min epinephrine infusion. Neurocognitive function improved after a period of coma, and progressively returned to baseline. The only neurological motor deficit was temporary right upper hemiparesis. Computed tomograms documented a right-sided hemispheric stroke, and reperfused arch vessels despite residual arch dissection (Fig. 2). The patient was discharged from the intensive care unit 36 days after surgery. 3. Discussion Medical therapy for type A acute aortic dissection yields unfavourable results. Although successful repair has been reported, preoperative stroke and especially coma are usually considered contraindications for immediate surgery w2–5x, in spite of the absence of criteria to define irreversible brain damage preoperatively. In the first patient, short-term delayed repair was performed after resuscitative measures in the comatose patient, and the timing of the indication was primarily based on the resumption of initially absent brainstem reflexes, whereas the second patient underwent immediate surgery. The postoperative period was temporarily characterized by profound coma, but late recovery was dramatic in apparently hopeless conditions. This suggests the possible benefits of immediate restoration of cerebral blood flow, even in case of altered or absent brainstem reflexes, and outlines the unreliability of the widely adopted Glas-gow coma scale for patient stratification, as previously outlined in a small case series by our group in which, the preservation of brainstem reflexes was considered a criterion to indicate emergent repair w5x. It might also be speculated that, in case of partial compression of the arch vessels, neurological dysfunction may have a higher potential for recovery. Finally, P300 peak latencies recorded with cognitive evoked potentials represent a useful tool to evaluate neurocognitive function, and are normally increased soon after open-heart operations w6x. In our first patient, the P300 latency recorded-2 months after the acute event, was only mildly increased when compared to healthy controls, and was similar to measurements after valve surgery. Our experience stresses the potential for reversibility of dissection-induced neurological injury, and confirms a higher likelihood of a more severe ischaemic insult in right-sided territories. Extensive arch surgery was not performed because of the absence of …