ABSTRACT
In this Letter, Mayuko Kurome and Valeri Zakhartchenko have been added to the author list (affiliated with Institute of Molecular Animal Breeding and Biotechnology, Gene Center, LMU Munich, Munich, Germany). The author list and 'Author contributions' section have been corrected online; see accompanying Amendment.
ABSTRACT
Heart transplantation is the only cure for patients with terminal cardiac failure, but the supply of allogeneic donor organs falls far short of the clinical need1-3. Xenotransplantation of genetically modified pig hearts has been discussed as a potential alternative4. Genetically multi-modified pig hearts that lack galactose-α1,3-galactose epitopes (α1,3-galactosyltransferase knockout) and express a human membrane cofactor protein (CD46) and human thrombomodulin have survived for up to 945 days after heterotopic abdominal transplantation in baboons5. This model demonstrated long-term acceptance of discordant xenografts with safe immunosuppression but did not predict their life-supporting function. Despite 25 years of extensive research, the maximum survival of a baboon after heart replacement with a porcine xenograft was only 57 days and this was achieved, to our knowledge, only once6. Here we show that α1,3-galactosyltransferase-knockout pig hearts that express human CD46 and thrombomodulin require non-ischaemic preservation with continuous perfusion and control of post-transplantation growth to ensure long-term orthotopic function of the xenograft in baboons, the most stringent preclinical xenotransplantation model. Consistent life-supporting function of xenografted hearts for up to 195 days is a milestone on the way to clinical cardiac xenotransplantation7.
Subject(s)
Heart Transplantation , Heterografts/transplantation , Papio , Swine , Transplantation, Heterologous , Animals , Antibodies/analysis , Antibodies/blood , Complement System Proteins/analysis , Enzymes/blood , Fibrin/analysis , Galactosyltransferases/deficiency , Galactosyltransferases/genetics , Heterografts/pathology , Humans , Liver/enzymology , Male , Membrane Cofactor Protein/genetics , Membrane Cofactor Protein/metabolism , Myocardium/enzymology , Necrosis , Perfusion , Platelet Count , Prothrombin Time , Thrombomodulin/genetics , Thrombomodulin/metabolism , Time FactorsABSTRACT
Currently, static cold storage (SCS) of hearts from donations after brainstem death remains the standard clinically. However, machine perfusion (MP) is considered an approach for donor organ management to extend the donor pool and/or increase the utilization rate. This review summarizes and critically assesses the available clinical data on MP in heart transplantation. We searched Medline (PubMed), Cochrane, Embase, and clinicaltrials.gov, along with reference lists of the included publications and identified 40 publications, including 18 articles, 17 conference abstracts, and five ongoing clinical trials. Two types of MP were used: hypothermic MP (HMP) and normothermic MP (NMP). Three studies evaluated HMP, and 32 evaluated NMP. Independent of the system, MP resulted in clinical outcomes comparable to traditional SCS. However, NMP seemed especially beneficial for high-risk cases and donation after circulatory death (DCD) hearts. Based on currently available data, MP is non-inferior to standard SCS. Additionally, single-centre studies suggest that NMP could preserve the hearts from donors outside standard acceptability criteria and DCD hearts with comparable results to SCS. Finally, HMP is theoretically safer and simpler to use than NMP. If a machine malfunction or user error occurs, NMP, which perfuses a beating heart, would have a narrower margin of safety. However, further well-designed studies need to be conducted to draw clear conclusions.
Subject(s)
Heart Transplantation , Organ Preservation , Heart , Humans , Organ Preservation/methods , Perfusion/methods , Tissue DonorsABSTRACT
BACKGROUND: Existing working heart models for ex vivo functional evaluation of donor hearts often use cardiac afterloads made up of discrete resistive and compliant elements. This approach limits the practicality of independently controlling systolic and diastolic aortic pressure to safely test the heart under multiple loading conditions. We present and investigate a novel afterload concept designed to enable such control. METHODS: Six â¼70 kg pig hearts were evaluated in vivo, then ex vivo in left-ventricular working mode using the presented afterload. Both in vivo and ex vivo, the hearts were evaluated at two exertion levels: at rest and following a 20 µg adrenaline bolus, while measuring aortic pressure and flow, left ventricular pressure and volume, and left atrial pressure. RESULTS: The afterload gave aortic pressure waveforms that matched the general shape of the in vivo measurements. A wide range of physiological systolic pressures (93 to 160 mm Hg) and diastolic pressures (73 to 113 mm Hg) were generated by the afterload. CONCLUSIONS: With the presented afterload concept, multiple physiological loading conditions could be tested ex vivo, and compared with the corresponding in vivo data. An additional control loop from the set pressure limits to the measured systolic and diastolic aortic pressure is proposed to address discrepancies observed between the set limits and the measured pressures.
Subject(s)
Heart Transplantation , Animals , Heart/physiology , Humans , Myocardial Contraction , Perfusion/methods , Swine , Tissue Donors , Ventricular Function, Left/physiologyABSTRACT
BACKGROUND: Successful preclinical transplantations of porcine hearts into baboon recipients are required before commencing clinical trials. Despite years of research, over half of the orthotopic cardiac xenografts were lost during the first 48 hours after transplantation, primarily caused by perioperative cardiac xenograft dysfunction (PCXD). To decrease the rate of PCXD, we adopted a preservation technique of cold non-ischemic perfusion for our ongoing pig-to-baboon cardiac xenotransplantation project. METHODS: Fourteen orthotopic cardiac xenotransplantation experiments were carried out with genetically modified juvenile pigs (GGTA1- KO/hCD46/hTBM) as donors and captive-bred baboons as recipients. Organ preservation was compared according to the two techniques applied: cold static ischemic cardioplegia (IC; n = 5) and cold non-ischemic continuous perfusion (CP; n = 9) with an oxygenated albumin-containing hyperoncotic cardioplegic solution containing nutrients, erythrocytes and hormones. Prior to surgery, we measured serum levels of preformed anti-non-Gal-antibodies. During surgery, hemodynamic parameters were monitored with transpulmonary thermodilution. Central venous blood gas analyses were taken at regular intervals to estimate oxygen extraction, as well as lactate production. After surgery, we measured troponine T and serum parameters of the recipient's kidney, liver and coagulation functions. RESULTS: In porcine grafts preserved with IC, we found significantly depressed systolic cardiac function after transplantation which did not recover despite increasing inotropic support. Postoperative oxygen extraction and lactate production were significantly increased. Troponin T, creatinine, aspartate aminotransferase levels were pathologically high, whereas prothrombin ratios were abnormally low. In three of five IC experiments, PCXD developed within 24 hours. By contrast, all nine hearts preserved with CP retained fully preserved systolic function, none showed any signs of PCXD. Oxygen extraction was within normal ranges; serum lactate as well as parameters of organ functions were only mildly elevated. Preformed anti-non-Gal-antibodies were similar in recipients receiving grafts from either IC or CP preservation. CONCLUSIONS: While standard ischemic cardioplegia solutions have been used with great success in human allotransplantation over many years, our data indicate that they are insufficient for preservation of porcine hearts transplanted into baboons: Ischemic storage caused severe impairment of cardiac function and decreased tissue oxygen supply, leading to multi-organ failure in more than half of the xenotransplantation experiments. In contrast, cold non-ischemic heart preservation with continuous perfusion reliably prevented early graft failure. Consistent survival in the perioperative phase is a prerequisite for preclinical long-term results after cardiac xenotransplantation.
Subject(s)
Heart Transplantation , Animals , Heterografts , Papio , Perfusion , Swine , Transplantation, HeterologousABSTRACT
Objectives. The aim of this study was to investigate endothelium dependent relaxation (EDR) in coronary artery and the myocardial contractility after 24 h of non-ischemic heart preservation (NIHP). Design. Explanted cardioplegic hearts from six pigs were preserved by NIHP for 24 h. The perfusion medium consisted of an albumin containing hyperoncotic cardioplegic nutrition-hormone solution with erythrocytes to a hematocrit of 10%. Coronary artery ring segments were then studied in organ baths. Thromboxane A2 was used for vasocontraction and Substance P to elicit endothelium dependent relaxation. A heart trabecula from the right ventricle was mounted in an organ bath and a special stimulation protocol was used to characterize myocardial contractility. Fresh cardioplegic hearts from 11 pigs were used as controls. The water content of the hearts was calculated. Results. There was no significant difference between NIHP and fresh controls regarding EDR (91.2 ± 1.2% vs 93.1 ± 1.8%). The contraction force, potentiation and calcium recirculation fraction did not differ between the groups. The water content of the myocardium was 79.3 ± 0.2% for NIHP and 79.5 ± 0.2% for controls. Conclusions. NIHP for 24 h keeps coronary artery EDR and myocardial contractility intact and causes no edema.
Subject(s)
Cardioplegic Solutions/pharmacology , Coronary Vessels/drug effects , Endothelium, Vascular/drug effects , Myocardial Contraction/drug effects , Organ Preservation/methods , Vasodilation/drug effects , Animals , Coronary Vessels/physiology , Endothelium, Vascular/physiology , Heart Arrest, Induced , Heart Transplantation , Sus scrofa , Time Factors , Tissue and Organ HarvestingABSTRACT
OBJECTIVES: The aim of this study was to investigate how high K+ concentrations can be safely used in cardioplegic solutions without causing severe coronary artery vasocontraction. DESIGN: Twenty-four 50 kg pigs were used. The distal part of the left anterior descending coronary artery was cut into ring segments and transferred into organ baths with Krebs solution bubbled with 95% O2 and 5% CO2. K+ concentrations between 16 and 127 mM were used to induce vasocontractions at 37, 22, 15, and 8 °C. Mg2+ (0-20 mM) were used to attenuate K+ induced vasocontractions. RESULTS: K+-Krebs solution 127 mM at 37 °C induced a strong, sustained vasocontraction defined as 100%. The contractions induced by 16, 23, 30 and 127 mM K+ were: 7.7, 38, 72 and 100% at 37 °C; 1.7, 7.4, 21 and 65% at 22 °C; 1, 6.6, 15 and 33% at 15 °C; 0.6, 2.1, 6 and 14% at 8 °C, respectively. Mg2+ reduced the K+-induced contraction at 37 °C in a concentration-dependent way and Mg2+ at 8 mM practically eliminated the risk for severe vasocontraction. CONCLUSIONS: Hypothermia (8 °C) abolishes coronary contraction induced by K+-cardioplegic solutions. In normothermic cardioplegia 8 mM Mg2+ prevents vasoconstriction.
Subject(s)
Cardioplegic Solutions/toxicity , Cold Temperature , Coronary Vasospasm/prevention & control , Coronary Vessels/drug effects , Hypothermia, Induced , Magnesium Chloride/pharmacology , Potassium Chloride/toxicity , Vasoconstriction/drug effects , Animals , Coronary Vasospasm/chemically induced , Coronary Vasospasm/physiopathology , Coronary Vessels/physiopathology , Dose-Response Relationship, Drug , In Vitro Techniques , Severity of Illness Index , Sus scrofaABSTRACT
The purpose of this concept study was to investigate the possibility of automatic mean arterial pressure (MAP) regulation in a porcine heart-beating brain death (BD) model. Hemodynamic stability of BD donors is necessary for maintaining acceptable quality of donated organs for transplantation. Manual stabilization is challenging, due to the lack of vasomotor function in BD donors. Closed-loop stabilization therefore has the potential of increasing availability of acceptable donor organs, and serves to indicate feasibility within less demanding patient groups. A dynamic model of nitroglycerine pharmacology, suitable for controller synthesis, was identified from an experiment involving an anesthetized pig, using a gradient-based output error method. The model was used to synthesize a robust PID controller for hypertension prevention, evaluated in a second experiment, on a second, brain dead, pig. Hypotension was simultaneously prevented using closed-loop controlled infusion of noradrenaline, by means of a previously published controller. A linear model of low order, with variable (uncertain) gain, was sufficient to describe the dynamics to be controlled. The robustly tuned PID controller utilized in the second experiment kept the MAP within a user-defined range. The system was able to prevent hypertension, exceeding a reference of 100 mmHg by more than 10%, during 98% of a 12 h experiment. This early work demonstrates feasibility of the investigated modelling and control synthesis approach, for the purpose of maintaining normotension in a porcine BD model. There remains a need to characterize individual variability, in order to ensure robust performance over the expected population.
Subject(s)
Anesthesia, Closed-Circuit/methods , Arterial Pressure , Brain Death , Monitoring, Physiologic/instrumentation , Monitoring, Physiologic/methods , Animals , Blood Gas Analysis , Hemodynamics , Humans , Hypertension , Hypotension , Models, Animal , Myocardial Contraction , SwineABSTRACT
BACKGROUND: Psychosocial factors are important for patients undergoing heart (HTx) or lung (LTx) transplantation and for their next of kin (NoK). AIM: To describe health-related quality of life (HRQoL; patients only), anxiety, depression, stress, coping ability, and burden (NoK only) for patients and their NoK before and up to 2 years after HTx or LTx. DESIGN: Adult patients (28 hearts and 26 lungs) and their appointed NoK were surveyed with questionnaires about specific psychosocial topics when they were accepted for the transplantation waiting list and 6 months, 1 year, and 2 years after transplantation. FINDINGS: Patients' coping ability and self-perceived health were low at baseline and improved over time after transplantation. However, lung patients took longer time to recover in terms of HRQoL, depression, and stress than heart patients. Similarly, NoK of lung patients experienced a higher burden and more stress 1 year after transplantation than NoK of heart patients. CONCLUSIONS: Healthcare professionals should be aware of the psychosocial challenges patients and their NoK face in daily living and provide support both before and after heart or lung transplantation.
Subject(s)
Anxiety Disorders/psychology , Depressive Disorder/psychology , Family/psychology , Heart Transplantation/adverse effects , Lung Transplantation/adverse effects , Quality of Life , Adaptation, Psychological , Adolescent , Adult , Aged , Anxiety Disorders/etiology , Depressive Disorder/etiology , Female , Follow-Up Studies , Humans , Longitudinal Studies , Male , Middle Aged , Prognosis , Risk Factors , Surveys and Questionnaires , Young AdultABSTRACT
OBJECTIVES: The aim of the study was to investigate if adequate preservation of coronary artery endothelium-dependent relaxation and contractility may be obtained after 8 hours of non-ischemic heart preservation. DESIGN: Porcine hearts were perfused for 8 hours at 8 °C, either in cycles of 15 minutes perfusion and 60 minutes non-perfusion, or by continuous perfusion. The perfusate consisted of a cardioplegic, hyperoncotic nutrition solution with oxygenated red cells, and the perfusion pressure was 20 mmHg. In organ baths, coronary artery segments from the preserved hearts were studied and compared to fresh controls. RESULTS: Endothelium-dependent relaxation and contractility were fully preserved after both intermittent and continuous perfusion, as compared to fresh controls. No myocardial edema was seen; water content of the myocardium was 79.5 ± 0.2%, 79.0 ± 0.4% and 79.0 ± 0.3% (ns) for fresh controls, intermittently perfused, and continuously perfused hearts, respectively. CONCLUSION: Intact endothelial and contractile function of coronary artery may be obtained after 8 hours of non-ischemic heart preservation.
Subject(s)
Cardioplegic Solutions/pharmacology , Coronary Vessels/drug effects , Endothelium, Vascular/drug effects , Organ Preservation Solutions/pharmacology , Organ Preservation/methods , Perfusion , Tissue and Organ Harvesting , Vasoconstriction/drug effects , Vasodilation/drug effects , Animals , Coronary Vessels/surgery , Endothelium, Vascular/surgery , In Vitro Techniques , Isolated Heart Preparation , Organ Preservation/adverse effects , Perfusion/adverse effects , Sus scrofa , Time Factors , Tissue and Organ Harvesting/adverse effectsABSTRACT
OBJECTIVES: The aim of this study was to demonstrate safe orthotopic transplantation of porcine donor hearts harvested 24 hours after brain death and preserved for 24 hours before transplantation. DESIGN: Circulatory normalization of brain dead (decapitated) pigs was obtained using a new pharmacological regimen (n = 10). The donor hearts were perfused at 8 °C in cycles of 15 min perfusion followed by 60 min without perfusion. The perfusate consisted of an albumin-containing hyperoncotic cardioplegic nutrition solution with hormones and erythrocytes. Orthotopic transplantation was done in 10 recipient pigs after 24 hours' preservation. Transplanted pigs were monitored for 24 hours, then an adrenaline stress test was done. RESULTS: All transplanted pigs were stable throughout the 24-hour observation period with mean aortic pressure around 80 mmHg and normal urine production. Mean right and left atrial pressures were in the range of 3-6 and 5-10 mmHg, respectively. Blood gases at 24 hours did not differ from baseline values. The adrenaline test showed a dose dependent response, with aortic pressure increasing from 98/70 to 220/150 mmHg and heart rate from 110 to 185 beats/min. CONCLUSION: Orthotopic transplantation of porcine hearts harvested 24 hours after brain death and preserved for 24 hours can be done safely.
Subject(s)
Heart Transplantation , Organ Preservation/methods , Perioperative Care/methods , Tissue and Organ Harvesting/methods , Animals , Brain Death , Disease Models, Animal , Heart Transplantation/adverse effects , Heart Transplantation/methods , Humans , Models, Anatomic , Swine , Tissue Survival , Treatment OutcomeABSTRACT
BACKGROUND: As pulmonary arterial hypertension (PAH) and chronic thromboembolic pulmonary hypertension (CTEPH) are debilitating and fatal diseases it is essential to increase the understanding of patients' experience of support. The aim was to describe patients' experiences of support while living with PAH or CTEPH. METHODS: Seventeen patients (13 women and four men) aged 28-73 years were strategically selected from a regional PAH centre and individually interviewed. The answers were analysed using qualitative content analysis. RESULTS: Three categories that describe patients' experiences of support emerged: Support linked to the healthcare; support linked to the private sphere; and support linked to persons outside the private sphere. CONCLUSION: Healthcare practitioners must work more in collaboration to detect patients' need for support and to develop the patient's own skills to manage daily life. The PAH teams should tailor interventions to provide emotional, informational and instrumental support and guidance to patients and their families.
Subject(s)
Delivery of Health Care , Hypertension, Pulmonary/therapy , Surveys and Questionnaires , Adult , Aged , Female , Humans , Male , Middle AgedABSTRACT
AIMS AND OBJECTIVES: To describe the patients' retrospective experiences of the information and support they received while on the heart or lung transplant waiting list. BACKGROUND: Patients differ in the way that they cope with the time spent waiting for a heart or lung transplant. Patients must already before the transplantation be taught about a new lifestyle, risk factors, medication, food restrictions and exercise, so they can take an active role and responsibility for disease management after transplantation. Little is known about patients' experiences of information and support in these situations. DESIGN: Qualitative descriptive design. METHODS: Sixteen patients (16-67 year) were strategically selected from one transplant centre in Sweden and interviewed six months after heart or lung transplantation. Using content analysis, transcribed data were organised into subcategories that reflected emerging categories. RESULTS: Three categories that describe patients' experiences of information and support have been identified: 'Achieving confidence and trust by information and support', 'Experiencing a lack of input and understanding' and 'Struggling with a life-threatening illness and an insecure future'. Each category consists of different subcategories. CONCLUSIONS: Information and support in connection to heart or lung transplantation are a complex and multifaceted issue involving patient-related, family-related, disease-related and treatment-related factors as well as experiences related to the social situation, the healthcare system and society. Transplant patients are very vulnerable, and a deeper understanding of patients' experiences should help healthcare providers in optimising the care for these very sick patients. RELEVANCE TO CLINICAL PRACTICE: A holistic approach to the patient is necessary in meeting the needs of patients with chronic illness, especially patients with children at home, as well as the needs of their families. An important implication is the necessity to enhance awareness about transplant patients in society in general, in particular in other institutions, by sharing knowledge and by improving cooperation.
Subject(s)
Heart Transplantation , Lung Transplantation , Waiting Lists , Adolescent , Adult , Aged , Female , Humans , Male , Middle Aged , Retrospective Studies , Sweden , Young AdultABSTRACT
BACKGROUND: During the first year after a cardiac event, many patients are offered participation in a cardiac rehabilitation programme, after which the patients are often not given the opportunity to continue to attend rehabilitation and secondary prevention programmes. AIM: This study describes the primary health care centres' (PHCC) resources regarding cardiac rehabilitation/secondary prevention programmes for coronary heart disease (CHD) patients in a southern Swedish region. METHOD: A questionnaire containing 26 dichotomous or multiple choice questions was sent to the responsible manager of all 137 public and private PHCCs in Region Skåne. Questionnaires from 91 (66%) of the PHCCs were completed and returned. RESULT: Few nurses at the PHCCs had special training regarding CHD (10%), cardiac rehabilitation (8%) or heart failure (32%). Twenty-one per cent of the physicians had special training regarding CHD. One third of the PHCCs did not offer long-term secondary prevention programmes, and few (6%) had any routines for offering socio-economic support to CHD patients. Comparison of private and public PHCCs showed that the private centres could not offer a physiotherapist (61 vs. 84%) or dietician (32 vs. 73%; p = 0.03) to the same extension as the public ones. Furthermore, the majority (91%) of PHCCs had no cooperation with patient organizations. CONCLUSIONS: The PHCCs need to improve the strategies and long-term rehabilitation programmes. Furthermore, they need to focus on education programme for the staff. The result revealed that the PHCCs lack resources, strategies and long-term care programmes for CHD patients.
Subject(s)
Health Resources , Myocardial Infarction/prevention & control , Myocardial Infarction/rehabilitation , Primary Health Care/organization & administration , Secondary Prevention , Humans , Surveys and Questionnaires , SwedenABSTRACT
Excitability and contraction of cardiac muscle from brain-dead donors critically influence the success of heart transplantation. Membrane physiology, Ca2+-handling, and force production of cardiac muscle and the contractile properties of coronary arteries were studied in hearts of brain-dead pigs. Cardiac muscle and vascular function after 12 h brain death (decapitation between C2 and C3) were compared with properties of fresh tissue. In both isolated cardiomyocytes (whole-cell patch clamp) and trabecular muscle (conventional microelectrodes), action potential duration was shorter in brain dead, compared to controls. Cellular shortening and Ca2+ transients were attenuated in the brain dead, and linked to lower mRNA expression of L-type calcium channels and a slightly lower ICa,L, current, as well as to a lower expression of phospholamban. The current-voltage relationship and the current above the equilibrium potential of the inward K+ (IK1) channel were altered in the brain-dead group, associated with lower mRNA expression of the Kir2.2 channel. Delayed K+ currents were detected (IKr, IKs) and were not different between groups. The transient outward K+ current (Ito) was not observed in the pig heart. Coronary arteries exhibited increased contractility and sensitivity to the thromboxane analogue (U46619), and unaltered endothelial relaxation. In conclusion, brain death involves changes in cardiac cellular excitation which might lower contractility after transplantation. Changes in the inward rectifier K+ channel can be associated with an increased risk for arrhythmia. Increased reactivity of coronary arteries may lead to increased risk of vascular spasm, although endothelial relaxant function was well preserved.
ABSTRACT
The effects of catecholamines on longitudinal displacements and intramural shear strain of the arterial wall are unexplored. Therefore, the common carotid artery of five anaesthetized pigs was investigated using an in-house developed noninvasive ultrasonic technique. The study protocol included intravenous infusion of low-dose epinephrine (ß-adrenoceptor activation), as well as intravenous boluses of norepinephrine (α-adrenoceptor activation). Further, the effects of ß-blockade (metoprolol) were studied. There were significant positive correlations between pulse pressure and longitudinal displacement of the intima-media complex (r = 0.72; P < 0.001), as well as between pulse pressure and intramural shear strain (r = 0.48; P < 0.001). Following administration of norepinephrine, the longitudinal displacement of the intima-media complex and intramural shear strain profoundly increased (median 190%, range 102-296%, and median 141%, range 101-182%, respectively, compared with baseline), also when given during ß-blockade (median 228%, range 133-266%, and median 158%, range 152-235%, respectively). During infusion of low-dose epinephrine, the longitudinal displacement of the intima-media complex and intramural shear strain decreased (median 88%, range 69-122%, and median 69%, range 47-117%, respectively, compared with baseline). In conclusion, the present study shows, for the first time, that the longitudinal displacement and intramural shear strain of the porcine carotid artery undergo profound changes in response to catecholamines. Increase in longitudinal displacements seems to be strongly related to α-adrenoceptor activation. Thus metoprolol is insufficient to counteract a profound increase in longitudinal displacement and intramural shear strain following a surge of norepinephrine.
Subject(s)
Carotid Artery, Common/drug effects , Catecholamines/pharmacology , Shear Strength/physiology , Adrenergic beta-1 Receptor Antagonists/pharmacology , Animals , Blood Pressure/drug effects , Blood Pressure/physiology , Carotid Artery, Common/diagnostic imaging , Carotid Artery, Common/physiology , Catecholamines/agonists , Catecholamines/antagonists & inhibitors , Metoprolol/pharmacology , Swine , Tunica Intima/diagnostic imaging , Tunica Intima/drug effects , Tunica Intima/physiology , Tunica Media/diagnostic imaging , Tunica Media/drug effects , Tunica Media/physiology , UltrasonographyABSTRACT
The aim of the study was to describe the patients' experiences of the information and support they received after being placed on the waiting list for a heart or lung transplant. The design was qualitative, and the critical incident technique was used. Incidents were collected via interviews with 21 patients. A total of 357 important events, both positive and negative, were identified and divided into two main groups: Body and mind and Information and support. The following subgroups emerged: chronic illness affects the patients, attitudes towards the future, impact of information, support from public organizations, and support from the private sphere. The patients showed knowledge of and involvement in the upcoming transplantation, which indicates that healthcare professionals managed to convey information and support effectively. By identifying the importance of factors such as body and mind and information and support for patients recently accepted for heart or lung transplantation, healthcare professionals are able to make specific improvements in the information and support that they provide. An important implication is to enhance the knowledge regarding transplant patients in other institutions and improve cooperation. Specific support programs to assist patients who have dependent children should be developed. Society needs to become more enlightened about organ donation and transplantation patients.
Subject(s)
Adaptation, Psychological , Heart Transplantation/psychology , Lung Transplantation/psychology , Patient Education as Topic , Patient-Centered Care , Social Support , Waiting Lists , Adult , Aged , Female , Heart Transplantation/education , Humans , Lung Transplantation/education , Male , Middle Aged , Needs Assessment , Qualitative Research , Time Factors , Tissue and Organ Procurement , Young AdultABSTRACT
BACKGROUND: Mechanical chest compressions (CCs) have been shown capable of maintaining circulation in humans suffering cardiac arrest for extensive periods of time. Reports have documented a visually normalized coronary blood flow during angiography in such cases (TIMI III flow), but it has never been actually measured. Only indirect measurements of the coronary circulation during cardiac arrest with on-going mechanical CCs have been performed previously through measurement of the coronary perfusion pressure (CPP). In this study our aim was to correlate average peak coronary flow velocity (APV) to CPP during mechanical CCs. METHODS: In a closed chest porcine model, cardiac arrest was established through electrically induced ventricular fibrillation (VF) in eleven pigs. After one minute, mechanical chest compressions were initiated and then maintained for 10 minutes upon which the pigs were defibrillated. Measurements of coronary blood flow in the left anterior descending artery were made at baseline and during VF with a catheter based Doppler flow fire measuring APV. Furthermore measurements of central (thoracic) venous and arterial pressures were also made in order to calculate the theoretical CPP. RESULTS: Average peak coronary flow velocity was significantly higher compared to baseline during mechanical chests compressions and this was observed during the entire period of mechanical chest compressions (12 - 39% above baseline). The APV slowly declined during the 10 min period of mechanical chest compressions, but was still higher than baseline at the end of mechanical chest compressions. CPP was simultaneously maintained at > 20 mmHg during the 10 minute episode of cardiac arrest. CONCLUSION: Our study showed good correlation between CPP and APV which was highly significant, during cardiac arrest with on-going mechanical CCs in a closed chest porcine model. In addition APV was even higher during mechanical CCs compared to baseline. Mechanical CCs can, at minimum, re-establish coronary blood flow in non-diseased coronary arteries during cardiac arrest.
Subject(s)
Blood Flow Velocity/physiology , Blood Pressure/physiology , Coronary Circulation/physiology , Heart Arrest/physiopathology , Heart Massage , Animals , Echocardiography, Doppler , Models, Animal , SwineABSTRACT
BACKGROUND: Myocardial infarction (MI) has long been seen as a male disease despite the fact that it is also a health problem for women. Factors that may influence their recovery, such as co-morbidity and requirements for support, have received less scientific attention. AIM: To explore and describe how women conceived their health and daily life 5 years after an MI. METHOD: An explorative and descriptive approach inspired by phenomenography was chosen as the design. The present study includes 12 women who have been described in earlier short-term studies. FINDINGS: The women described how the MI caused limitations in their lives even 5 years after the MI. They experienced physical restrictions, fatigue and also other health complaints. Furthermore, the older women suffered from various co-morbidities such as diabetes, kidney disease, high blood pressure, and stroke. Some women did not perceive their heart disease to interfere in daily life. Many of the women had thoughts about having a new MI. Furthermore, some women were grateful and described it as having a second opportunity. CONCLUSION: The present study indicates how women in the recovery process 5 years after an MI still need support to continue with lifestyle changes. The women continue to struggle with different kinds of issues, such as financial stress, co-morbidity and side effects of medication. Support from the health care only in the first year after the MI is not enough. The women should benefit from the possibility to visit or consult professionals in primary care with knowledge of CHD.
Subject(s)
Myocardial Infarction/physiopathology , Women's Health , Adult , Aged , Aged, 80 and over , Female , Humans , Middle AgedABSTRACT
PURPOSE: Ischemic myocardial contracture (IMC) or "stone heart" is a condition with rapid onset following circulatory death. It inhibits transplantability of hearts donated upon circulatory death (DCD). We investigate the effectiveness of hemodynamic normalization upon withdrawal of life-sustaining therapy (WLST) in a large-animal controlled DCD model, with the hypothesis that reduction in cardiac work delays the onset of IMC. METHODS: A large-animal study was conducted comprising of a control group ([Formula: see text]) receiving no therapy upon WLST, and a test group ([Formula: see text]) subjected to a protocol for fully automated computer-controlled hemodynamic drug administration. Onset of IMC within 1 h following circulatory death defined the primary end-point. Cardiac work estimates based on pressure-volume loop concepts were developed and used to provide insight into the effectiveness of the proposed computer-controlled therapy. RESULTS: No test group individual developed IMC within [Formula: see text], whereas all control group individuals did (4/6 within [Formula: see text]). CONCLUSION: Automatic dosing of hemodynamic drugs in the controlled DCD context has the potential to prevent onset of IMC up to [Formula: see text], enabling ethical and medically safe organ procurement. This has the potential to increase the use of DCD heart transplantation, which has been widely recognized as a means of meeting the growing demand for donor hearts.