Valve-related complications after mechanical heart valve implantation

The effect of a smartphone-based application on the self-efficacy of heart valve surgery patients and their family caregivers` burden: a randomized clinical trial

BACKGROUND

Heart valve replacement has many complications that affect patients and their family caregivers. Increasing patients' self-efficacy in dealing with complications and reducing the care burden of their caregivers are among the critical factors that impact their quality of life. Today, smartphone Apps allow access to reliable information without time and place restrictions. It also facilitates teaching and learning through low-cost and easily accessible methods.

OBJECTIVE

This study was conducted to examine the effect of a smartphone App on the care burden of family caregivers and self-efficacy of patients undergoing heart valve surgery.

METHODOLOGY

A randomized clinical trial study with a pre-test / post-test design was conducted. Sixty patients undergoing mechanical heart valve surgery were referred to the Shahid Modarres Hospital and PT clinic in Tehran, and their family caregivers were randomly divided into intervention and control groups. The App was installed on the patients' smartphones for educational purposes, and they were given 8 weeks to use it. Sullivan's cardiac self-efficacy questionnaire and Novak and Guest's care burden questionnaire were completed for patients and their caregivers in both groups before and after the intervention, respectively. Data was statistically analyzed using descriptive and inferential statistics through SPSS-18 software.

FINDINGS

There was no statistically significant difference between the two groups regarding demographic characteristics and the mean scores of self-efficacy and care burden before the intervention. However, after the intervention, the mean self-efficacy score increased to 47.43 ± 5.43 in the intervention group and 32.23 ± 3.25 in the control group, showing a significant improvement in patients' self-efficacy in the intervention group (P < 0.001). Although the mean self-efficacy score slightly increased in the control group, this increase was not statistically significant (P = 0.094). Furthermore, the mean score of care burden of caregivers after the intervention increased to 45.33 ± 6.34 in the intervention group and 53.86 ± 6.80 in the control group, showing a significant decrease in the care burden of caregivers in the intervention group compared to those in the control group (P < 0.001).

CONCLUSION

Based on the results, the designed smartphone App improved the self-efficacy of patients undergoing heart valve surgery while reducing the care burden of their family caregivers. Therefore, this App is recommended due to its effectiveness, ease of use, and low cost.

TRIAL REGISTRATION

Prospectively registered with the Iranian Registry of Clinical Trials on 11 March 2023; registration code: IRCT20210714051889N1.

Case Report: Post-operative mitral valve replacement complicating with a large cardiac mass and the role of TEE in Imaging

Background

Postoperative complications are an integral part of valve surgery. Common complications include hematomas, bleeding, valve dehiscence, paravalvular leak, and acute PV thrombosis. With the available data from published articles, the rate of all valve-related complications is 0.7 to 3.5% per patient annually. [1] The pathology involved is multifactorial, often blood vessel injury leading to bleeding and hematoma. Although postoperative complications are evident, incidental diagnosis of a cardiac mass in an asymptomatic and hemodynamically stable patient postoperatively is crucial, requiring non-invasive imaging for immediate surgical action.

Case presentation

A woman in her 50s presented with chief complaints of worsening dyspnoea with suddenonset and chest pain. Clinical findings showed apex shifted downward and outward, wide split S2, and a mid systolic murmur radiating to the mid axillary line. Twelve-lead ECG showed LA enlargement, that aligned with X-ray findings. 2D Echocardiography revealed MVP with severe MR and a dilated LV. The patient underwent successful mitral valve replacement as per ACC/AHA class I recommendation. However, postoperative TTE showed a remarkably large mass measuring 5.6 cm*4.6 cm in the RA. Reexploration was performed, followed by mass excision. Plenty of organized clots were seen compressing the RA. TEE showed no evidence of mass. Following stabilization,the patient was discharged considering optimal INR values and prosthetic valve function assessed by echocardiography. The patient's symptoms improved during the first follow-up.

Conclusion

Although postoperative cardiac complications are common, appropriate diagnosis with TTE and TEE has benefited surgeons. TEE-guided reexploration aids surgeons in decision-making and strategic approaches. Failure to diagnose such complications in asymptomatic patients can ultimately complicate the procedure. Henceforth, sonographers must be skilled in the detection and identification of unusual complications to guide redo interventions. Such an approach minimizes mortality, redo procedures, and avoids CPB hence reducing long-term prognosis and outcomes with valve replacement.

Emergence of graphene as a novel nanomaterial for cardiovascular applications

Cardiovascular diseases (CDs) are the foremost cause of death worldwide. Several promising therapeutic methods have been developed for this approach, including pharmacological, surgical intervention, cell therapy, or biomaterial implantation since heart tissue is incapable of regenerating and healing on its own. The best treatment for heart failure to date is heart transplantation and invasive surgical intervention, despite their invasiveness, donor limitations, and the possibility of being rejected by the patient's immune system. To address these challenges, research is being conducted on less invasive and efficient methods. Consequently, graphene-based materials (GBMs) have attracted a great deal of interest in the last decade because of their exceptional mechanical, electrical, chemical, antibacterial, and biocompatibility properties. An overview of GBMs' applications in the cardiovascular system has been presented in this article. Following a brief explanation of graphene and its derivatives' properties, the potential of GBMs to improve and restore cardiovascular system function by using them as cardiac tissue engineering, stents, vascular bypass grafts,and heart valve has been discussed.

Revisiting echocardiographic features of prosthetic heart valves: the necessity of correct differentiation of mono-leaflet vs. bileaflet mechanical heart valves in a case report

BACKGROUND

Mechanical heart valve replacement is a standard treatment for severe valvular disorders. The use of mono-leaflet valves has decreased recently. Recognizing the echocardiographic features of mono-leaflet and bileaflet valves is crucial for accurate complication diagnosis and proper management.

CASE PRESENTATION

A 65-year-old female with mono-leaflet mitral and bileaflet tricuspid valves underwent an echocardiographic assessment. This simple educational case provides a unique opportunity to compare the echocardiographic features of these valves within a single patient.

CONCLUSION

There is a crucial need for clinicians, particularly those in training, to differentiate between mono-leaflet and bileaflet mechanical heart valves adeptly. With mono-leaflet valves decreasing in prevalence, proficiency in recognizing the echocardiographic nuances of each type is imperative. Failure to do so may result in misdiagnoses and inappropriate management. This underscores the significance of continuous education and vigilance in echocardiographic assessments to ensure optimal patient care.

Experimental observation on a new chimney-shaped mechanical valve completely implanted above the mitral annulus in animals

Current commercially available prosthetic valves suffer from limited size, high requirements for implantation technique, subvalvular structural destruction, and valve dysfunction due to proliferation of fibrous endothelial tissue. This study aims to perform the preclinical large animal experiments for surgically implanting a chimney-shaped artificial mechanical heart valve with zero left ventricular occupancy, which fully accommodates the movement of the valve leaflets in the valve frame and realizes completely supra-annular surgical implantation. A total of 7 sheep underwent the replacement of artificial valve, and 5 sheep survived normally until anatomical examination. The mechanical properties of these artificial mitral valves remain functionally normal. There was no obvious thromboembolism around the artificial valve and in the important organs. The tissue layer of suture ring was completely organized and endothelialized, and the thickness of tissue layer was about 0.6-1.0 mm. The follow-up of echocardiography showed that the left ventricular ejection fraction was normal (60-70%) before and 6 months after operation. The results of transvalvular pressure gradient and blood flow velocity of artificial valve were normal. Left ventricular retrograde angiography showed that the artificial valve was completely located in the left atrium with good position and normal opening and closing. There was no obvious perivalvular leakage and other abnormalities. At 3 and 6 months, there were no obvious abnormalities in blood routine test, liver and kidney function, and other indexes. The new chimney-shaped artificial mechanical valve implanted completely above the mitral annulus had good wear resistance, histocompatibility, and antithrombotic and hemodynamic performance.

A Global Systematic Review of Open Heart Valvular Surgery in Resource-Limited Settings

BACKGROUND

Many obstacles challenge the establishment and expansion of cardiac surgery in low- and middle-income countries, despite the unmet cardiac surgical needs. One challenge has been providing adequate follow-up care to monitor anticoagulation, manage morbidity, and prevent mortality. This systematic review describes outcomes after valvular cardiac surgery and focuses on strategies for prolonged follow-up care in resource-constrained settings.

METHODS

Studies published between 2012 and 2022 were collected from Embase and the Cochrane Library. Article inclusion criteria were adolescent and adult patients, open heart valvular surgery, and analysis of at least 1 postoperative outcome at least 30 days postoperatively. Studies that focused on pediatric patients, pregnant patients, transcatheter procedures, in-hospital outcomes, and nonvalvular surgical procedures were excluded. Descriptive statistics were assessed, and articles were summarized after abstract screening, full-text review, and data extraction.

RESULTS

Sixty-seven relevant publications were identified after screening. The most commonly studied regions were Asia (46%), Africa (36%), and Latin America (9%). Rheumatic heart disease was the most commonly studied valvular disease (70%). Reported outcomes included mortality, surgical reintervention, and thrombotic events. Follow-up duration ranged from 30 days to 144 months; 11 studies reported a follow-up length of 12 months.

CONCLUSIONS

Addressing the unmet cardiac care needs requires a multifaceted approach that leverages telemedicine technology, enhances medical infrastructure, and aligns advocacy efforts. Learning from the cost-effective establishment of cardiac surgery in low- and middle-income countries, we can apply past innovations to foster sustainable cardiac surgical capacity.

Early and long-term outcomes of mitral valve replacement with mechanical valve in rheumatic heart disease

Background

Rheumatic fever and rheumatic heart disease is endemic in India. Mitral valve replacement with mechanical valve is the commonest surgical procedure performed in rheumatic heart disease (RHD). However, there are no studies reporting the long-term outcomes of mechanical mitral valve replacement in rheumatic heart disease from India.

Objective

The primary objective of the study was to look at the long-term survival following mechanical mitral valve replacement in RHD. The secondary objectives included follow up complications and event-free survival.

Methods

For this study, 238 patients who underwent mitral valve replacement with TTK Chitra™ valve from 1st January 2006 to 31st December 2018 for RHD were included for analysis and reporting. The median follow-up period was 3371.50 days (9.3 years). Total follow-up was 2044 patient-years.

Results

The mean age of the study population was 39.72 ± 10.48 years (range: 18-68 years). Out of 238 patients operated, 155 patients (65.12%) were alive and 69 patients (28.99%) were dead, and 14 patients (5.88%) were lost to follow-up. The operative mortality was 6 (2.52%) and the follow-up mortality was 63 (26.47%). The reasons for follow-up mortality were cardiac complications in 22 (34.9%) patients, valve-related complications in 18 (28.5%) patients, sudden unexplained death in 13 (20.6%) patients, and non-valve/ non-cardiac death in 10patients (15.8%). The one-year survival was 94.0%, five-year survival was 83.6%, ten-year survival was 70.6% and 15-year survival was 62.9%. During follow-up, valve-related events occurred in 123(52%) patients. The 15-year event-free survival was 33.0%.

Conclusions

The long term outcome of mechanical valve replacement of the mitral valve in RHD patients was less than favorable. Both cardiac complications and mechanical valve related complications reduced their survival.

Valve-sparing aortic root replacement using a straight tube graft (David I procedure)

OBJECTIVES

We present our 25-year experience with valve-sparing aortic root replacement using a straight tube graft (David-I).

METHODS

From 1993 to 2019, 677 patients (median age, 56.0 years; range, 42-65) underwent the David-I procedure with a straight tube graft. A total of 24 different surgeons performed these operations. Marfan syndrome was present in 111 patients (16.4%), and bicuspid aortic valve was present in 71 patients (10.5%). Aortic root aneurysm was present in 544 patients (80.4%), and acute dissection was present in 133 patients (19.6%).

RESULTS

Ministernotomy was used in 57 patients (8.4%). Additional cusp plasty was performed in 84 patients (12.4%). Concomitant procedures were coronary artery bypass grafting (n = 122, 18.0%), mitral valve surgery (n = 34, 5%), proximal arch replacement (n = 125, 18.4%), subtotal arch replacement (n = 43, 6.4%), and total arch replacement (n = 102, 15.1%). Overall in-hospital mortality was 4.0% (n = 27), and perioperative stroke occurred in 26 patients (3.8%). Postoperative echocardiography showed aortic insufficiency less than I° in 600 of 623 (96.3%). The 1-, 5-, 10-, 15-, and 20-year survivals were 97%, 92%, 79%, 68%, and 50%, respectively. The rates for freedom from aortic valve-related reoperation at 1, 5, 10, 15, and 20 years were 97%, 92%, 87%, 84%, and 80%, respectively. Multivariate Cox regression analysis identified age (odds ratio, 0.974; 95% confidence interval, 0.957-0.992; P = .004), senior surgeon (odds ratio, 0.546; 95% confidence interval, 0.305-0.979; P = .042), and residual postoperative aortic insufficiency (odds ratio, 4.864; 95% confidence interval, 1.124-21.052; P = .034) as independent risk factors for aortic valve-related reoperation.

CONCLUSIONS

The aortic valve-sparing David-I procedure can be performed with very low perioperative morbidity and mortality. The short- and long-term results are excellent. The straight tube graft does not lead to increased leaflet erosion. This procedure is reproducible by multiple surgeons.

Systematic review and meta-analysis of time-to-event long-term outcomes following the Ross procedure

Background

The optimal aortic valve substitute for non-elderly adults remains controversial. Recently, considerable data on the Ross procedure have accumulated. This study aimed to analyze long-term outcomes following the Ross procedure from the current literature using a meta-analysis of time-to-event outcomes.

Methods

A literature search was performed with MEDLINE, EMBASE, Cochrane Library, Web of Science, and Google Scholar through June 2022; studies reporting clinical outcomes of the Ross procedure beyond 20 years were included for analysis. The outcomes of interest were late survival and freedom from surgical or percutaneous reintervention of the autograft or right ventricular outflow tract (RVOT).

Results

Six studies, including 4,910 patients (3,601 males), were identified and analyzed. Survival rate at 5, 10, 15, and 20 years was 99.9%±0.1%, 97.6%±0.5%, 94.3%±0.9%, and 87.4%±1.9%. Freedom from autograft reintervention at 5, 10, 15, and 20 years was 97.7%±0.5%, 95.3%±0.7%, 91.4%±1.2%, 84.8%±2.5%. Freedom from RVOT reintervention was 99.0%±0.3%, 99.0%±0.3%, 97.5%±0.7%, 93.3%±1.8%. Freedom from any valve reintervention (either autograft or RVOT) at 5, 10, 15, and 20 years was 95.8%±0.6%, 92.6%±0.9%, 88.5%±1.2%, 80.8%±2.5%.

Conclusions

This meta-analysis demonstrated that the Ross procedure was confirmed to provide excellent survival despite the need for reintervention of autograft or RVOT in approximately 20% of patients at 20 years.

The Quality of Life in Patients With Valve Prosthesis After Undergoing Surgery for Valvular Heart Diseases

Background and objective Surgery for valvular heart disease by valve replacement procedures has become one of the most frequently performed cardiac operations to improve the quality of life (QoL). Its long-term outcomes are assessed using the quality-of-life index (QLI). This study aimed to evaluate the QoL in patients who received valve prostheses after surgery for valvular heart diseases at King Abdulaziz University in Jeddah from 2010 to 2023. Methods This was a descriptive cross-sectional study of 59 patients aged 18 years or older who underwent surgical mitral and aortic valve replacement, involving either mechanical or tissue valves, from January 2010 to May 2023 They were selected using a non-probability convenient sampling technique. Their medical records were reviewed and the participants were interviewed via phone using the World Health Organization Quality of Life-BREF (WHOQOL-BREF) questionnaire, which was used to measure the QoL of patients (https://neurotoolkit.com/whoqol-bref/). Results The study found that the QoL of the participants varied across different domains. The psychological domain had the highest mean score of 79.76, while the physical domain had the lowest mean score of 61.5. The other domains, - social, environmental, and spiritual - had mean scores of 68.05, 69.9, and 73.25, respectively. There was a statistically significant association between the QoL and nationality and chronic diseases. However, the duration after surgery and the type of valve did not significantly correlate with the QoL in the different domains. Conclusion Based on our findings, heart valve replacement improves the QoL of patients. Healthcare organizations and providers should aim to improve the management of chronic diseases to optimize outcomes.

Estimating the Potential Economic Impact of Tissue Valve Replacement for Heart Valve Disease in China: Patient-Level and Population-Level Cost-Benefit Simulation Analyses

OBJECTIVES

This study seeks to estimate the potential societal economic impact of treating patients with heart valve disease (HVD) in China with surgical tissue valve replacement versus mechanical valves.

METHODS

This societal economic cost-benefit evaluation is based on an individual simulation model for subgroups of patients with HVD that is also aggregated to a macrosocietal model. The individual simulation model was developed to estimate the likely economic impact of surgical aortic valve replacement (SAVR) with tissue versus mechanical valves for different subgroups among all eligible patients with HVD over their remaining lifetimes. Clinical inputs were informed by health claims database analysis, expert clinical opinion, and published literature. Epidemiological inputs and demographic inputs were sourced from the published literature and the China Statistical Yearbook 2020. Health gains were valued at 3 times the average national income.

RESULTS

Projected total lifetime economic gains were greater for patients receiving tissue valves. Costs were reported in 2021 US dollars. The average lifetime net economic gain for tissue valve patients was $51 736 (20.0% more than for mechanical valve patients). Increasing the use of tissue valves to 50% among all eligible patients with HVD would provide aggregate long-term economic gains of $167 billion during their remaining lifetimes. The economic gains from greater tissue valve use were due to avoiding anticoagulation monitoring costs, improved quality of life, and greater post-SAVR labor force participation.

CONCLUSION

Increased use of tissue valves versus mechanical values in SAVR procedures in China would be likely to generate a substantial societal economic gain.

Cost-Effectiveness of the Pharmacist-Managed Warfarin Therapy vs. Standard Care for Patients With Mechanical Mitral Valve Prostheses: An Egyptian Healthcare Perspective

Background

Despite warfarin therapy had been used for decades for patients with mechanical mitral valve prostheses (MMVPs), serious and life-threatening complications are still reported worldwide with a significant economic burden. This study is aimed at assessing the clinical and the cost-effectiveness of adopting pharmacist-managed warfarin therapy (PMWT) services for optimizing warfarin treatment in Egypt.

Methods

A prospective randomized trial in which 59 patients with MMVPs were randomly assigned to receive the PMWT services or the standard care and followed up for 1 year. The primary outcome was percentage time in the therapeutic range (TTR). For the cost-effectiveness analysis, a Markov cohort process model with nine mutually exclusive health states was developed from a medical provider’s perspective. A lifetime horizon was applied. All costs and outcomes were discounted at 3.5% annually.

Results

The study results revealed a significantly higher median TTR in the intervention group as compared to the control group; 96.8% [interquartile range (IQR) 77.9–100%] vs. 73.1% (52.7–95.1%), respectively, p = 0.008. A significant association between standard care and poor anticoagulation control (p = 0.021) was demonstrated by the multivariate regression analysis. For the cost-effectiveness analysis, the total cumulative quality-adjusted life-years (QALYs) and total costs per patient were 21.53 and 10.43; 436.38 and 1,242.25 United States dollar (USD) in the intervention and the control groups, respectively, with an incremental cost-effectiveness ratio (ICER) of −72.5796 for the intervention group.

Conclusion

The PMWT strategy was proven to provide a significantly better anticoagulation control and to be a cost-saving approach in Egyptian patients with MMVPs. Nevertheless, the dominance of this strategy is sustained by maintaining the therapeutic International Normalized Ratio (INR) control within the recommended range. Our findings will benefit Egyptian policy-makers who may seek novel health strategies for better resource allocation.

Clinical Trial Registration

[ClinicalTrials.gov], identifier [NCT04409613].

An unusual cause of acute mitral regurgitation in TTK Chitra heart valve prosthesis

Structural failure of mechanical heart valve was a known feature when it was evolving in the 1960s and 1970s. With the advent of pyrolytic carbon and a better design, it is a rare entity with present valves. We report a case of disc fracture leading to acute mitral regurgitation in TTK Chitra heart valve prosthesis (CHVP) (TTK Healthcare Limited, India) heart valve, 6 years after its implantation in mitral position.

Early and Late-Term Follow-Up Results of Patients Diagnosed with Aortic Aneurysm or Aortic Dissection with Aortic Regurgitation Undergoing Aortic Valve Repair or Valve-Sparing Aortic Surgery

INTRODUCTION

Valve-reimplantation and remodelling techniques used in aortic reconstruction provide successful early, mid, and long-term results. We present our early and late-term experience with 110 patients with aortic regurgitation (AR) who underwent aortic valve repair (AVr) or valve-sparing aortic root surgeries (VSARS) due to aortic dissection or aortic aneurysm.

METHODS

Nine hundred eighty-two patients who underwent aneurysm or dissection surgery and aortic valve surgery between April 1997 and January 2017 were analysed using the patient database. A total of 110 patients with AR who underwent AVr or VSARS due to aortic dissection or aortic aneurysm were included in the study.

RESULTS

In the postoperative period, a decrease was observed in AR compared to the preoperative period (P<0.001); there was an increase in postoperative ejection fraction (EF) compared to the preoperative values (P<0.005) and a significant decrease in postoperative left ventricle diameters compared to the preoperative values (P<0.001). Kaplan-Meier analysis revealed one, two, four, and five-year freedom from moderate-severe AR as 95%, 91%, 87%, and 70%, respectively. Freedom from reoperation in one, two, and five years were 97.9%, 93.6%, and 81%, respectively. Eight patients (7.4%) underwent AVr during follow-up. Out of the remaining 100 patients, 13 (12%) had minimum AR, 52 (48%) had 1st-2nd degree AR, and 35 (32%) had 2nd-3rd degree AR during follow-up.

CONCLUSION

For the purpose of maintaining the native valve tissue, preserving the EF and the left ventricular end-diastolic diameter, valve-sparing surgeries should be preferred for appropriate patients.

Aortic valve-sparing root replacement with Tirone E. David's reimplantation technique: single-centre 25-year experience

 

OBJECTIVES

Tirone E. David described aortic valve-sparing root reimplantion (AVSRR) almost 30 years ago. At our centre, we adopted this operation in 1993, and since then, we have performed >700 operations over a time period of >25 years. In this report, we present our single-centre experience.

METHODS

Between 1993 and 2019, a total of 732 patients underwent AVSRR at our centre. The mean age was 53 ± 15 and 522 (71%) were male. Marfan syndrome was present in 117 (16%) patients and bicuspid aortic valve in 81 (11%). The indication for surgery was aortic root aneurysm in 588 (80%) patients and acute aortic dissection in 144 (20%) patients.

RESULTS

Mini-sternotomy was performed in 74 (10%) patients. A straight tube graft (David I) was used in 677 (92%) and a Valsalva-graft in 55 (8%) patients. Cusp plasty was done in 83 (11%) patients. Concomitant cardiac procedures were performed in 438 (60%) patients. Overall in-hospital mortality was 3.8% (n = 29) and 1.9% (n = 11) in elective cases. Postoperative echocardiography was available for 671 patients and showed aortic insufficiency (AI) ≤I° in 647 (96%) patients. The mean follow-up time was 10 ± 6.7 years and comprised a total of 7307 patient-years. The 1-, 5-, 10- and 15-year survival rates were: 93%, 88%, 77% and 65%, respectively. The rates for freedom from valve-related reoperation at 1, 5, 10 and 15 years after initial surgery were 97%, 93%, 88% and 85%, respectively. Cox regression analysis identified age [odds ratio (OR) = 0.975, 95% confidence interval (CI) = 0.955-0.995, P = 0.016], hyperlipidaemia (OR = 1.980, 95% CI = 1.175-3.335, P = 0.010), preoperative level of left ventricular ejection function (OR = 1.749, 95% CI = 1.024-2.987, P = 0.041) and postoperative degree of AI (OR = 1.880, 95% CI = 1.532-2.308, P ≤ 0.001) as risk factors for the future AI or reoperation.

CONCLUSIONS

David procedure can be performed extremely safely, with low risks for perioperative morbidity and mortality, both in elective situations via minimally invasive access and in emergent settings for acute aortic type A dissection. Regarding long-term outcome, David's AVSRR seems to provide excellent clinical results and sustainable function of the aortic valve in the majority of patients almost 3 decades after its introduction.

[Clinical results of cardiac valve repair with bicuspid full-flow mechanical prosthesis 'MedEng-ST']

Prosthetic repair of cardiac valves with artificial mechanical prostheses is ubiquitously performed using prostheses consisting of two cusps (bicuspidal). Several years ago, new bicuspid full-flow prostheses appeared on the market. From the first use they immediately proved reliable, with stable haemodynamic characteristics. At the Interregional Clinical and Diagnostic Centre, bicuspid full-flow mechanical prostheses 'MedEng-ST' have been used since 2017. We carried out a retrospective follow up of 84 patients subjected to prosthetic repair of cardiac valves with full-flow prostheses 'MedEng-ST' in mitral and aortic positions. There were no prosthesis-associated or procedural complications during follow up. Neither were there major complications in the postoperative period. All complications were related to peculiarities of the approach to the heart. We assessed the functional parameters of the heart by standard echocardiography. The obtained findings demonstrated good haemodynamic parameters on the 'MedEng-ST' prostheses, improved intracardiac haemodynamics, which eventually had a beneficial effect on the patients' clinical picture. The transprosthetic gradients had stable parameters with a decrease in time when placing the 'MedEng-ST' prosthesis into the aortic position (p≤0.05). Proceeding from the obtained results, as well as taking into account the absence of thromboembolic events it may be stated that the proposed design of the device is universal for replacement of the aortic and mitral valves of the heart. Based on the obtained findings of the study we recommend to use the 'MedEng'ST' prostheses in clinical practice. Further studies are required for more convincing data and explicit recommendations.

Single and multi-functional coating strategies for enhancing the biocompatibility and tissue integration of blood-contacting medical implants

Device-associated clot formation and poor tissue integration are ongoing problems with permanent and temporary implantable medical devices. These complications lead to increased rates of mortality and morbidity and impose a burden on healthcare systems. In this review, we outline the current approaches for developing single and multi-functional surface coating techniques that aim to circumvent the limitations associated with existing blood-contacting medical devices. We focus on surface coatings that possess dual hemocompatibility and biofunctionality features and discuss their advantages and shortcomings to providing a biocompatible and biodynamic interface between the medical implant and blood. Lastly, we outline the newly developed surface modification techniques that use lubricant-infused coatings and discuss their unique potential and limitations in mitigating medical device-associated complications.

Managing the Adult Patient with Congenital Heart Disease

The focus of this article is noncardiac surgery in the adult with congenital heart disease (CHD). The purpose is to provide the general and pediatric anesthesiologist with a basic overview of the most common congenital cardiac lesions, their long-term sequelae, and expected perioperative concerns during noncardiac surgery. Because of the very heterogeneous nature of CHD, it is difficult to make a single article a comprehensive guide for every lesion and its associated perioperative concerns. The authors hope to provide those who are not specifically trained in congenital cardiac anesthesia the basic principles and a greater understanding of each defect.

A New Nanocomposite Copolymer Based On Functionalised Graphene Oxide for Development of Heart Valves

Polymeric heart valves seem to be an attractive alternative to mechanical and biological prostheses as they are more durable, due to the superior properties of novel polymers, and have the biocompatibility and hemodynamics comparable to tissue substitutes. This study reports a comprehensive assessment of a nanocomposite based on the functionalised graphene oxide and poly(carbonate-urea)urethane with the trade name "Hastalex" in comparison with GORE-TEX, a commercial polymer routinely used for cardiovascular medical devices. Experimental data have proved that GORE-TEX has a 2.5-fold (longitudinal direction) and 3.5-fold (transverse direction) lower ultimate tensile strength in comparison with Hastalex (p < 0.05). The contact angles of Hastalex surfaces (85.2 ± 1.1°) significantly (p < 0.05) are lower than those of GORE-TEX (127.1 ± 6.8°). The highest number of viable cells Ea.hy 926 is on the Hastalex surface exceeding 7.5-fold when compared with the GORE-TEX surface (p < 0.001). The platelet deformation index for GORE-TEX is 2-fold higher than that of Hastalex polymer (p < 0.05). Calcium content is greater for GORE-TEX (8.4 mg/g) in comparison with Hastalex (0.55 mg/g). The results of this study have proven that Hastalex meets the main standards required for manufacturing artificial heart valves and has superior mechanical, hemocompatibility and calcific resistance properties in comparison with GORE-TEX.

Increased Risk of Ischemic Stroke After Treatment of Infective Endocarditis: A Danish, Nationwide, Propensity Score-Matched Cohort Study

BACKGROUND

Several studies have reported a high risk of ischemic stroke (IS) during the acute phase of infective endocarditis (IE). The long-term risk of IS after IE, however, is not fully illuminated.

METHODS

This Danish, nationwide, register-based, propensity score-matched cohort study used Cox regression to estimate hazard ratios (HRs) of IS for persons with vs without a history of left-sided IE, from 1977 to 2015.

RESULTS

We followed 9312 patients exposed to a first-time IE and 91 996 nonexposed, matched control persons. Compared to persons without IE, patients with a history of IE had a significantly increased risk of IS; the risk was highest during the first 4 weeks after IE diagnosis (HR 57.20, 95% confidence interval [CI] 45.58-71.78; P < .0001) and a moderately elevated risk persisted until 2 years after IE (4 weeks to 3 months after IE, HR 5.40, 95% CI 4.11-7.19; 3 months to 2 years after IE, HR 1.73, 95% CI 1.48-2.01). Mediation analyses showed that the higher risk of IS the first 2 years after IE could not be explained by atrial fibrillation (AF) or inserted mechanical valves in IE patients. In the period from 4 weeks to 3 months after IE diagnosis, patients treated with anticoagulative therapy had a lower risk of IS (HR 0.30, 95% CI .10-0.96; P = .04).

CONCLUSIONS

Patients with a history of IE had an increased risk of IS for up to 2 years after IE diagnosis. The increased risk was unrelated to AF and inserted mechanical valves. During the initial phase after IE, patients taking an anticoagulative medication had a lower risk of IS.

Vector Flow Imaging of the Ascending Aorta in Patients with Tricuspid and Bicuspid Aortic Valve Stenosis Treated with Biological and Mechanical Implants

Aortic valve stenosis (AS) is treated with biological prostheses (BPs) and mechanical prostheses (MPs). Vector flow imaging (VFI), an angle-independent ultrasound method, can quantify flow complexity (vector concentration (VC)) and secondary rotation (SR). Ten patients (mean age: 70.7 y) with tricuspid AS scheduled for BPs, 10 patients (mean age: 56.2 y) with bicuspid AS scheduled for MPs and 10 patients (mean age: 63.9 y) with normal aortic valves were scanned intra-operatively on the ascending aorta with VFI and conventional spectral Doppler. Bicuspid AS (peak systolic velocity (PSV): 380.9 cm/s, SR: 16.7 Hz, VC: 0.21) had more complex flow (p < 0.02) than tricuspid AS (PSV: 346.1 cm/s, SR: 17.1 Hz, VC: 0.33). Both groups had more complex and faster flow (p < 0.0001) than normal aortic valve patients (PSV: 124.0 cm/s, SR: 4.3 Hz, VC: 0.79). VC (r = 0.87) and SR (r = 0.89) correlated to PSV. After surgery, flow parameters changed (p < 0.0001) for patients with MPs (PSV: 250.4 cm/s, SR: 9.8 Hz, VC: 0.54) and BPs (PSV: 232.4 cm/s, SR: 12.5 Hz, VC: 0.61), with MPs having slower SR (p < 0.01). None of the implants had normal flow (p < 0.0001). In conclusion, VFI can provide new flow parameters for AS and implant assessment.

"A Tale of Two Cities": Anticoagulation Management in Patients with Atrial Fibrillation and Prosthetic Valves in the Era of Direct Oral Anticoagulants

Valvular heart disease and atrial fibrillation often coexist. Oral vitamin K antagonists have represented the main anticoagulation management for antithrombotic prevention in this setting for decades. Novel direct oral anticoagulants (DOACs) are a new class of drugs and currently, due to their well-established efficacy and security, they represent the main therapeutic option in non-valvular atrial fibrillation. Some new evidences are exploring the role of DOACs in patients with valvular atrial fibrillation (mechanical and biological prosthetic valves). In this review we explore the data available in the medical literature to establish the actual role of DOACs in patients with valvular heart disease and atrial fibrillation.

Metallic embolus to the brain in a patient with mechanical heart valves: an extremely rare complication

A 46-year-old man with a medical history of rheumatic valve disease underwent mitral and aortic valve replacements with On-X and CarboMedics Top Hat supra-annular mechanical valves, respectively. Seven months after the valve replacement surgery, the patient presented with dizziness. A CT scan of the brain was done as part of a thorough workup of dizziness. The CT scan revealed a small metallic density in the M2 branch of the right middle cerebral artery. The metallic density was believed to be a metallic embolus that originated from the mechanical valves or the suturing material, that is, Cor-Knot fastener. Although in our case, the dizziness was believed to be the result of benign paroxysmal positional vertigo, through this case, we aim to highlight this extremely rare structural complication of mechanical valves. This complication can have serious and potentially fatal consequences such as embolic component-related stroke or another organ infarction.

Comparison of Incidence, Predictors, and Outcomes of Early Infective Endocarditis after Transcatheter Aortic Valve Implantation Versus Surgical Aortic Valve Replacement in the United States

Infective endocarditis (IE) of prosthetic or bioprosthetic heart valves is a serious complication associated with significant morbidity and mortality. Data on the incidence, risk factors, and outcomes of IE after transcatheter aortic valve implantation (TAVI) in the United States are limited. We used the 2013 to 2014 Nationwide Readmissions Databases to determine the incidence of early IE after TAVI and surgical aortic valve replacement (SAVR) in the US. Clinical characteristics, independent predictors, and outcomes of patients with IE post-TAVI were examined. In 29,306 TAVI and 66,077 SAVR patients, the incidence rates of early IE were 1.7% (95% confidence interval [CI] 1.5% to 1.9%) and 2.5% (95% CI 2.3% to 2.9%) per person-year, respectively. In a propensity-matched cohort of 15,138 TAVI and 15,030 SAVR patients (weighted), there were no significant differences in the incidence rates of IE (1.7% [95% CI 1.4% to 2.0%] vs 1.9% [95% CI 1.6% to 2.2%] per person-year, log-rank p = 0.29) or in the median (interquartile range) time to IE (91 [48 to 146] vs 92 [61 to 214] days, p = 0.13). Staphylococcus (30.4%), Streptococcus (29.9%), and Enterococcus (20.5%) were the most common causative organisms of IE post-TAVI. Younger age, history of heart failure, need for permanent pacemaker placement, cardiac arrest, major bleeding, and sepsis during the index TAVI hospitalization were independently associated with an increased risk of IE. In-hospital mortality rate during readmission for IE was 15.6%. In conclusion, in a nationally representative cohort of TAVI patients in the US, the incidence rate of early IE was 1.7% per person-year. Age, co-morbid conditions, invasive procedures, and complications during the index hospitalization were associated with incident IE post-TAVI.

Recurrent Hemorrhagic Conversion of Ischemic Stroke in a Patient with Mechanical Heart Valve: A Case Report and Literature Review

The authors present a unique case of recurrent stroke, discovered to be secondary to hemorrhagic conversion of microemboli from a mechanical aortic valve despite anticoagulation with Coumadin. The complexity of this case was magnified by the patient’s young age, a mechanical heart valve (MHV), and a need for anticoagulation to maintain MHV patency in a setting of potentially life-threatening intracranial hemorrhage. Anticoagulant and antiplatelet therapy are risk factors for hemorrhagic conversion post-cerebral ischemia; however, the pathophysiology underlying endothelial cell dysfunction causing red blood cell extravasation is an active area of basic and clinical research. The need for randomized clinical trials to aid in the creation of standardized treatment protocol continues to go unmet. Consequently, there is marked variation in therapeutic approaches to treating intracranial hemorrhage in patients with an MHV. Unfortunately, patients with an MHV are considered at high thromboembolic (TE) risk, and these patients are often excluded from clinical trials of acute stroke due to their increased TE potential. The authors feel this case represents an example of endothelial dysfunction secondary to microthrombotic events originating from an MHV, which caused ischemic stroke with hemorrhagic conversion complicated by the need for anticoagulation for an MHV. This case offers a definitive treatment algorithm for a complex clinical dilemma.

Haemodynamic improvement of older, previously replaced mechanical mitral valves by removal of the subvalvular pannus in redo cardiac surgery

Patients requiring redo cardiac surgery for diseased heart valves other than mitral valves may show increased pressure gradients and reduced valve areas of previously placed mechanical mitral valves due to subvalvular pannus formation. We treated four women who had mechanical mitral valves inserted greater than or equal to 20 years earlier and who presented with circular pannus that protruded into the lower margin of the valve ring but did not impede leaflet motion. Pannus removal improved the haemodynamic function of the mitral valve.

Severe tricuspid regurgitation after mitral valve surgery: the risk factors and results of the aggressive application of prophylactic tricuspid valve repair

Purpose

This study aimed to examine the risk factors for severe postoperative tricuspid regurgitation (TR) in patients undergoing mitral valve surgery. We also studied the effects of prophylactic tricuspid valve repair (TVR) on severe postoperative TR.

Methods

We retrospectively studied 125 patients without severe TR who underwent mitral valve surgery from 1987 to 2006. Patients did not undergo TVR before 1998 (the early period, n = 54). In 1998 (the late period, n = 71), patients with a preoperative tricuspid annular diameter of ≥35 mm underwent TVR using an annuloplasty ring (n = 52).

Results

In the analysis of the early period, the rates of freedom from severe TR at 10 and 20 years after surgery were 76 and 59 %, respectively. A multivariate analysis identified moderate preoperative TR as a significant risk factor for severe TR. In the late period, none of the 52 patients who underwent TVR developed severe TR. However, 4/19 patients who did not undergo TVR developed severe TR, and all of these four patients had a preoperative tricuspid annular diameter of ≤35 mm.

Conclusions

Moderate preoperative TR is a significant risk factor for severe postoperative TR in patients undergoing mitral valve surgery. The aggressive application of TVR can prevent severe postoperative TR; however, tricuspid annular dilatation might not be a good indicator for TVR.

Pannus-related prosthetic valve dysfunction. Case report

Pannus-related prosthetic valve dysfunction, a complication of mechanical prosthetic valve replacement, is rare, with a slowly progressive evolution, but it can be acute, severe, requiring surgical reintervention. We present the case of a patient with a mechanical single disc aortic prosthesis, with moderate prosthesis-patient mismatch, minor pannus found on previous ultrasound examinations, who presented to our service with angina pain with a duration of 1 hour, subsequently interpreted as non-ST segment elevation myocardial infarction (NSTEMI) syndrome. Coronarography showed normal epicardial coronary arteries, an ample movement of the prosthetic disc, without evidence of coronary thromboembolism, and Gated Single-Photon Emission Computerized Tomography (SPECT) with Technetium (Tc)-99m detected no perfusion defects. Transthoracic echocardiography (TTE) evidenced a dysfunctional prosthesis due to a subvalvular mass; transesophageal echocardiography (TOE) showed the interference of this mass, with a pannus appearance, with the closure of the prosthetic disc. Under conditions of repeated angina episodes, under anticoagulant treatment, surgery was performed, with the intraoperative confirmation of pannus and its removal. Postoperative evolution was favorable. This case reflects the diagnostic and therapeutic management problems of pannus-related prosthetic valve dysfunction.

Fifteen-year experience with the Bicarbon heart valve prosthesis in a single center

Background

The purpose of this study was to evaluate retrospectively the clinical performance of the Bicarbon valve (Sorin Biomedica Cardio, Saluggia, Italy) implanted at our center in Japan.

Methods

Between January 1997 and December 2011, 415 patients in our institution were implanted with the Bicarbon valve. Nine of these recipients were excluded from the study because they had already undergone valve implantation and received a Bicarbon valve in a different position. The remaining patients were analyzed for evaluation of the postoperative clinical outcomes. Of the 406 patients (mean age 60.2 ± 11.7 years), 179 underwent aortic valve replacement (AVR), 149 mitral valve replacement (MVR), and 78 both aortic and mitral valve replacement (DVR).

Results

There were 10 early deaths (2.5 %: 4 in the AVR group and 6 in the MVR group). Three hundred eighty-nine patients were followed up (95.8 % completeness of follow-up) with a mean follow-up of 6.6 ± 4.2 years overall (AVR 6.8 ± 4.2, MVR, 6.7 ± 4.4, and DVR 5.7 ± 3.4 years) and a cumulative follow-up of 2661 patient-years (1214, 1001, and 446 patient-years for AVR, MVR, and DVR, respectively). Ninety-nine patients died (3.7 % per patient-year: 22 valve-related and 77 valve-unrelated deaths). Survival at 10 years was 74.1 ± 4.0 % in the AVR group, 73.7 ± 4.2 % in the MVR group, and 61.0 ± 7.9 % in the DVR group. The linearized incidence of thromboembolic complications, bleeding complications, prosthetic valve endocarditis, paravalvular leaks, and sudden death in all patients was 0.5 %, 0.5 %, 0.2 %, 0.2 %, and 0.4 % per patient-year, respectively. The incidence of valve-related complications and reoperation was 1.6 % and 0.4 %, respectively. No other valve-related complications were observed.

Conclusions

The Bicarbon prosthetic heart valve has shown excellent clinical results and is associated with a low incidence of valve-related complications.

Current progress in tissue engineering of heart valves: multiscale problems, multiscale solutions

INTRODUCTION

Heart valve disease is an increasingly prevalent and clinically serious condition. There are no clinically effective biological diagnostics or treatment strategies. The only recourse available is replacement with a prosthetic valve, but the inability of these devices to grow or respond biologically to their environments necessitates multiple resizing surgeries and life-long coagulation treatment, especially in children. Tissue engineering has a unique opportunity to impact heart valve disease by providing a living valve conduit, capable of growth and biological integration.

AREAS COVERED

This review will cover current tissue engineering strategies in fabricating heart valves and their progress towards the clinic, including molded scaffolds using naturally derived or synthetic polymers, decellularization, electrospinning, 3D bioprinting, hybrid techniques, and in vivo engineering.

EXPERT OPINION

Whereas much progress has been made to create functional living heart valves, a clinically viable product is not yet realized. The next leap in engineered living heart valves will require a deeper understanding of how the natural multi-scale structural and biological heterogeneity of the tissue ensures its efficient function. Related, improved fabrication strategies must be developed that can replicate this de novo complexity, which is likely instructive for appropriate cell differentiation and remodeling whether seeded with autologous stem cells in vitro or endogenously recruited cells.