Rapid-deployment aortic valve replacement during challenging aortic valve reoperation: a case report.

A previously implanted stenotic aortic valve bioprosthesis with stenotic coronary ostia and intramyocardial calcium was surgically debrided resulting in disruption of the left outflow track. A rapid-deployment aortic valve bioprosthesis was implanted to cover the remnant aortic valve annulus, ensure open coronary ostia, and secure a well-functioning aortic valve bioprosthesis with low postoperative gradient.

Health-related quality of life is improved after coronary artery bypass graft surgery: a 1-year follow-up study.

OBJECTIVES: The purpose of this study was to detect changes in QoL after coronary artery bypass grafting surgeries (CABG) in one year, and to identify the possible predictive factors associated with the change. DESIGN: A single-center prospective study of 501 patients was conducted between 2013 and 2018 using the EQ-5D VAS questionnaire for estimating the QoL. The patients filled in a questionnaire preoperatively, at 6 and at 12 months postoperatively. Univariate and multivariable logistic regression analyses were used to find out if certain pre-selected factors or EQ5D dimensions had independent effects on the observed EQ VAS scores. RESULTS: QoL improved in all EQ-5D dimensions and in EQ VAS scores at 6 and at 12 months: the greatest changes in the number of reported problems were in the dimensions "mobility" (-34.2%, p<.001), "self-care" (-36.7%, p=.001) and "pain or discomfort" (-31.0%, p<.001). With the multivariable regression model, we could show that normal left ventricle ejection fraction (LVEF) and improvement in mobility and pain/discomfort dimensions were in association with improvement of EQ VAS score at 6 months. At 12 months this association was no longer detectable. CONCLUSIONS: CABG procedure can improve patient's QoL when judged with EQ5D dimensions and related overall self-rated health (VAS). This improvement was seen both at 6 and at 12 months postoperatively. Except for LVEF, the other patient-specific risk factors we examined did not seem to affect QoL in the long term.

Improved health-related quality of life in patients 6 and 12 months after surgical aortic valve replacement.

Objectives. Quality of life (QoL) is possibly the most important variable for the patient when subjective results of heart procedures are evaluated. The purpose of this study was to analyze the change in the quality of life 1 year after surgical aortic valve replacement (SAVR). Design. A Finnish single-center prospective cohort intervention study was performed from 2013 to 2018. QoL was assessed with the EQ-5D-3L VAS questionnaire before surgery and 6 and 12 months after surgery. We used univariate analysis to assess the change in the number of people experiencing problems and logistic regression analysis to assess the patients' characteristics on the change in QoL. Results. At one year follow-up, patients' quality of life improved in all EQ-5D dimensions. The greatest decreases in patients experiencing problems 12 months after surgery occurred in the dimension "mobility" (-24.1% change in reporting problems, p < .01), "self-care" (-32.9%, p < .01), and "pain or discomfort" (-25.7%, p < .01). Before surgery mean of EQ visual analogue scale (VAS, from 0 to 100) was 63.0 (SD 17.7, n = 604), and 12 months after surgery 81.2 (SD 13.8, n = 367, p < .001). In multivariable analysis, preoperative obesity was associated with better quality of life (OR 3.39, 95% CI 1.007-11.439) in "daily activities" and patients' higher operative risk was associated with better "self-care" after surgery. Conclusions. SAVR can improve the 1-year quality of life in all dimensions of EQ-5D and self-rated overall health (VAS).

Effect of particulate contamination on adhesive ability and repellence in two species of ant (Hymenoptera; Formicidae).

Tarsal adhesive pads are crucial for the ability of insects to traverse their natural environment. Previous studies have demonstrated that for both hairy and smooth adhesive pads, significant reduction in adhesion can occur because of contamination of these pads by wax crystals present on plant surfaces or synthetic microspheres. In this paper, we focus on the smooth adhesive pads of ants and study systematically how particulate contamination and the subsequent loss of adhesion depends on particle size, particle surface energy, humidity and species size. To this end, workers of ant species Polyrhachis dives and Myrmica scabrinodis (Hymenoptera; Formicidae) were presented with loose synthetic powder barriers with a range of powder diameters (1-500 µm) and surface energies (PTFE or glass), which they would have to cross in order to escape the experimental arena. The barrier experiments were conducted for a range of humidities (10-70%). Experimental results and scanning electron microscopy confirm that particulate powders adversely affect the adhesive ability of both species of ant on smooth substrates via contamination of the arolia. Specifically, the loss of adhesion was found to depend strongly on particle diameter, but only weakly on particle type, with the greatest loss occurring for particle diameters smaller than the claw dimensions of each species, and no effect of humidity was found. We also observed that ants were repelled by the powder barriers which led to a decrease of adhesion prior to their eventual crossing, suggesting that insect antennae may play a role in probing the mechanical fragility of substrates before crossing them.

Forearm vessel atherosclerosis. A harbinger of carotid disease?

OBJECTIVES: Atherosclerosis is a systemic disease affecting several vessels of the body. Coronary artery patients requiring bypass surgery have increased prevalence of carotid artery atherosclerosis which is known to increase operative risk in coronary artery bypass surgery (CABG). Radial artery is often screened for grafting purposes preoperatively. Our aim was to find out whether atherosclerotic changes in forearm vessels are correlated and could reveal risk to carotid artery disease. DESIGN: Eighty-five patients planned for elective CABG were examined with ultrasonography preoperatively. Biplane ultrasonographic scanning was performed on forearm arteries and both carotid arteries. RESULTS: Eleven patients had pathologic changes in the wall of forearm vessels. Carotid artery disease was found on 19 patients. Forearm vessel pathology was found to have correlation to carotid artery disease. When forearm arteries show atherosclerotic pathology the risk of having carotid disease is at least five-fold, in subgroups even higher. CONCLUSIONS: Forearm arterial pathology is correlated to carotid artery disease. When forearm vessel pathology is evident in preoperative examination, scanning of the carotid vessels should be considered.

Non-harvestable radial artery. A bilateral problem?

Since radial artery is preferably harvested from a non-dominant hand, our aim was to study whether there are contraindications for radial artery harvest in the dominant hand if the radial artery of the other hand is not suitable for harvesting. Thirty-three patients scheduled to coronary artery bypass grafting with contraindication for radial artery harvest in the non-dominant hand underwent Allen test, upper arm Doppler ultrasonography and digital pletysmography. In ultrasonography, both anatomical and circulatory measurements were performed. Both hands were then compared to each other. Furthermore, twelve control patients without contraindication for radial artery harvest in the non-dominant hand were examined. All 33 patients had contraindication for radial artery harvest in the non-dominant hand. Twenty-four (73%) had contraindication in the dominant hand as well. In terms of morphology, there was no statistically significant difference between the hands but circulatory parameters as a group suggested contraindication. Among controls, four patients (33%) had contraindication in the dominant hand. In the case of a non-harvestable radial artery in a hand there is clearly an increased risk for contraindication for radial artery harvest also in the other hand.

Is the Allen test reliable enough?

OBJECTIVE: The Allen test is a widely used screening method of hand circulation. Our aim was to study whether the Allen test alone gives sufficient information for harvesting the radial artery in coronary artery bypass grafting. METHODS: One hundred and forty-five patients scheduled for coronary artery bypass grafting underwent the Allen test, upper arm Doppler ultrasonography and digital plethysmography. In ultrasonography both anatomical and circulatory measurements were performed. The Allen test was then compared with more objective tests and sensitivity; specificity and diagnostic accuracy were calculated. RESULTS: Most of the patients had a negative Allen test, but 23% were positive (abnormal). Ultrasound scanning revealed anatomical anomalies in 10 patients and circulatory deficits in 17 patients. Thirteen patients had both circulatory and anatomical abnormalities. Sensitivity of the Allen test was 73.2% and specificity 97.1% based on our findings. There were no abnormalities in the recovery of the arms with harvested radial grafts. CONCLUSIONS: The Allen test is a good and valid screening test for the circulation of the hand. If the Allen test is negative it is safe to harvest the radial artery. If it is positive further examinations are needed to ensure safe harvesting of the radial artery.

Engineered wettability in tree capillaries.

The water-conducting network of capillaries in plants has evolved to cope with the frequent occurrence of cavitation, which leads to air-filled capillaries that are unable to function in water transport. However, the material from which the capillaries are constructed is not perfectly wetted by water, contrary to what is often assumed and to what one might expect in an optimal design. I demonstrate that nature is able to overcome this deficiency by engineering the roughness of the capillary walls to achieve near complete wetting, a strategy analogous to that used in the natural engineering of the wettability of plant leaves and insect wings. The results provide an appealing answer to the long-standing debate on the function of wall sculpturing in plant capillaries, and may provide biomimetic clues for the engineering of wettability in technological applications such as microfluidics.

Mixing and condensation in a wet granular medium.

We have studied the effect of small amounts of added liquid on the dynamic behavior of a granular system consisting of a mixture of glass beads of two different sizes. Segregation of the large beads to the top of the sample is found to depend in a nontrivial way on the liquid content. A transition to viscoplastic behavior occurs at a critical liquid content, which depends upon the bead size. We show that this transition can be interpreted as a condensation due to the hysteretic liquid bridge forces connecting the beads, and we provide the corresponding phase diagram.

Evaporation and instabilities of microscopic capillary bridges.

The formation and disappearance of liquid bridges between two surfaces can occur either through equilibrium or nonequilibrium processes. In the first instance, the bridge molecules are in thermodynamic equilibrium with the surrounding vapor medium. In the second, chemical potential gradients result in material transfer; mechanical instabilities, because of van der Waals force jumps on approach or a Rayleigh instability on rapid separation, may trigger irreversible film coalescence or bridge snapping. We have studied the growth and disappearance mechanisms of laterally microscopic liquid bridges of three hydrocarbon liquids in slit-like pores. At rapid slit-opening rates, the bridges rupture by means of a mechanical instability described by the Young-Laplace equation. Noncontinuum but apparently reversible behavior is observed when a bridge is held at nanoscopic surface separations H close to the thermodynamic equilibrium Kelvin length, 2r(K)costheta, where r(K) is the Kelvin radius and theta is the contact angle. During the course of slow evaporation (at H > 2r(K)costheta) and subsequent regrowth by capillary condensation (at H < 2r(K)costheta), the refractive index of the bridge may vary continuously and reversibly between that of the bulk liquid and vapor. The evaporation process becomes irreversible only at the very final stage of evaporation, when the refractive index of the fluid attains virtually that of the vapor. Measured refractive index profiles and the time-dependence of evaporating neck diameters also seem to differ from predictions based on a continuum picture of bridge evaporation far from the critical point. We discuss these findings in terms of the probable density profiles in evolving liquid bridges.