Outcomes of Transvenous Lead Extraction in a Referral Center in Northern Israel.

BACKGROUND: Cardiac implantable electronic devices (CIEDs) are increasingly being used; thus, there is an increasing need for transvenous lead extraction (TLE). OBJECTIVES: To summarize our experience with TLE at single referral center in northern Israel. METHODS: The study included all patients who underwent TLE at our center between 2019 and 2022, regardless of the indication. RESULTS: The cohort included 50 patients. The mean age was 69 ± 10.36 years; 78% were males. A total of 99 electrodes were targeted. The mean number of electrodes was 1.96 (range 1-4) per patient. The time between lead implantation and extraction ranged between 1.1 and 34 years with an average of 8.14 ± 5.71 years (median of 7.5 years). Complete lead removal was achieved in 98% of patients and in 98.99% of leads. The complete procedural success rate as well as the clinical procedural success rate was 96%. The procedural failure rate was 4% (1 patient died 2 days after the index procedure and 1 patient remained with large portion of lead). The indication for TLE was infection in 78% of the cohort group. Powered mechanical sheaths were used in 36 patients (72%), laser sheaths in 27 (54%), and a combination of laser and mechanical sheaths in 16 (32%). CONCLUSIONS: The clinical and procedural success rates of TLE, primarily for CEID-related infection, were high. A combination of laser and mechanical sheaths was needed in one-third of patients.

The Effects of Preoperative Pain Education on Pain Severity in Cardiac Surgery Patients: A Pilot Randomized Control Trial.

BACKGROUND: There is minimal research on the effect of individualized preoperative education on postoperative pain and postoperative pain medication intake. AIM: The study objective was to assess the effect of individually tailored preoperative education on postoperative pain severity, number of pain breakthroughs, and use of pain medication in participants receiving the intervention compared to controls. METHODS: A pilot study with 200 participants was conducted. The experimental group received an informational booklet and discussed their ideas surrounding pain and pain medication with the researcher. Controls received no intervention. Postoperative pain severity was measured by a Numerical Rating System (NRS), which was divided into mild (NRS 1-3), moderate (NRS 4-6), and severe (NRS 7-10). RESULTS: In the participant cohort, 68.8% of participants were male, and the average age was 60.48±10.7. Average postoperative 48-hour cumulative pain scores were lower in those who received the intervention compared to controls; 50.0 (IQR 35.8-60.0) vs. 65 (IQR 51.0-73.0; p < .01) participants who received the intervention had less frequent pain breakthroughs when compared to controls (3.0 [IQR 2.0-5.0] vs. 6.0 [IQR 4.0-8.0; p < .01]). There was no significant difference in the amount of pain medication taken by either group. CONCLUSIONS: Participants who receive individualized preoperative pain education are more likely to have decreased postoperative pain.

Relationships among norepinephrine levels, exercise capacity, and chronotropic responses in heart failure patients.

In heart failure (HF) patients, the pathophysiological mechanisms of severe exercise intolerance and impaired exercise capacity are related to both central and peripheral abnormalities. The central abnormalities in HF patients include impaired cardiac function and chronotropic incompetence (CI). Indeed, CI, the inability to adequately increase heart rate (HR) from rest to exercise often exhibited by HF patients, is related to activation of the sympathetic nervous system (SNS) yielding a rise in circulating norepinephrine (NE). CI may result from downregulation of ß-adrenergic receptors, ß-blocker usage, high baseline HR, or due to a combination of factors. This paper discusses the role of elevated NE in altering chronotropic responses in HF patients and consequently resulting in impaired exercise capacity. We suggest that future research should focus on the potential treatment of CI with rate-adaptive pacing, using a sensor to measure physical activity, without inducing deleterious hormonal activation of the sympathetic system.

Predictors of prolonged hospitalization in modified sternoplasty following postoperative mediastinitis.

BACKGROUND AND AIM: Deep sternal wound infection (DSWI) is a serious complication following cardiac surgery, and demands early intervention as any delay in diagnosis and management may lead to increased morbidity and mortality. DSWI is associated with increased length of hospitalization (LOH) and economic burden in this patient population. The aim of this study was to determine predictors for increased length of hospitalization in patients who underwent the Modified Sternoplasty technique for deep sternal wound infection following cardiac surgery. METHODS: A retrospective study was undertaken on data from patients who underwent the Modified Sternoplasty surgery for DSWI between September 2010 and January 2020. Patients' characteristics that were recorded included medical history, type of the original heart surgery, length of hospitalizations, and risk factors including hyperlipidemia, diabetes mellitus and hypertension, and morbidity and mortality rates following the Modified Sternoplasty. RESULTS: Sixty-eight patients underwent the Modified Sternoplasty surgery with an average length of hospitalization of 24.63 + 22.09 days. Multivariable analysis showed that only gender was considered a predictor of length of hospitalization when controlling for comorbidities, with average length of hospitalization longer for women than men (35.4 vs. 20.9, p = .04). CONCLUSION: The Modified Sternoplasty surgery is a novel surgical technique for managing DSWI complicated by sternal dehiscence with exposed heart and great vessels. Female gender was associated with increased length of hospitalization in our patient cohort, with average length of hospitalization for women almost twice that of males.

Clinical factors and pre-surgical depression scores predict pain intensity in cardiac surgery patients.

BACKGROUND: Severe pain is prevalent in cardiac surgery patients and can increase cardiac complications, morbidity and mortality. The objectives of the study were to assess perioperative pain intensity and to assess predictors of pain post-cardiac surgery, including clinical characteristics and depression. METHODS: A total of 98 cardiac surgery patients were included in the study. Pain intensity was assessed using a Numerical Rating System. Pain was measured one day pre-operatively and recorded daily from Post-operative Day 2 to Day 7. Clinical data were recorded and depression scores were assessed using the Center for Epidemiological Study of Depression (CES-D). RESULTS: Pain intensity increased significantly during hospitalization from pre-operative levels, surging at 2 days post-operatively. Predictors of high pain intensity were high pre-operative CES-D scores, female gender, cardiac function, smoking and high body mass index (BMI). Significantly higher pre-operative CES-D scores were found in patients with severe pain compared to patients with no pain to moderate pain (18.23 ± 1.80 vs 12.84 ± 1.22, p = 0.01 pre-operatively). Patients with severe pain (NRS 7-10) had significantly higher levels of white blood cells (WBC) compared to patients with no pain-moderate pain (NRS 0-6), (p = 0.01). However, CES-D scores were only weakly correlated maximum WBC levels perioperatively. CONCLUSION: Pain intensity significantly increased following surgery, and was associated with depressive symptoms, female sex, cardiac function, BMI, and smoking. These factors may serve as a basis for identification and intervention to help prevent the transition from acute pain to chronic pain.

The routine use of preoperative non-contrast chest computerized tomography and carotid arteries Doppler prior to cardiac surgery.

INTRODUCTION: There is no consensus as to which patients should undergo Non-Contrast Chest Computerized Tomography (NCCCT) and carotid arteries Doppler (CD) prior to cardiac surgery. The objective of this study was to examine whether preoperative imaging modalities provide clinical benefits and a change in surgical strategy. METHODS: We routinely performed NCCCT and CD in all non-urgent cardiac surgery patients. Major NCCCT/CD findings related to cardiovascular findings (aortic calcification/atherosclerosis, carotid artery plaque/stenosis), or other incidental findings (lung kidney, thyroid, adrenal, gastrointestinal sites etc.) were documented. The results were divided into 3 categories: (A) findings requiring both changes in surgical strategy and post-operative evaluation/treatment; (B) findings requiring changes in surgical strategy, but not requiring a specific post-operative evaluation/treatment; (C) findings not requiring changes in surgical strategy but requiring post-operative evaluation/treatment. RESULTS: In this cohort, 93 (18.6%) out of 500 patients had significant cardiac and extra-cardiac findings on NCCCT and/or CD. Among the 93 patients with significant findings, 33.33% (31 patients, 6.2% of all patients) were in group A, 7.5% (7 patients, 1.4% of all patients) were in group B, and 59.14% (55 patients, 11% of all patients) were in group C. Change in surgical strategies included, for example, switching from planned on-pump Coronary Artery Bypass Graft surgery (CABG) to off-pump CABG and performing additional procedures to the originally planned heart surgery. CONCLUSION: Routine preoperative NCCCT and CD evaluation in all non-urgent cardiac surgical patients is an effective measure for uncovering cardiac and extra-cardiac findings prior to surgery.

The Modified Sternoplasty: A Novel Surgical Technique for Treating Mediastinitis.

Deep sternal wound infection (DSWI) is one of the most complex and devastating complications post cardiac surgery. We present here the modified sternoplasty, a novel surgical technique for treating DSWI post cardiac surgery. The modified sternoplasty includes debridement and sternal refixation via bilateral longitudinal stainless-steel wires that are placed parasternally along the ribs at the midclavicular or anterior axillary line, followed by six to eight horizontal stainless-steel wires that are anchored laterally and directly into the ribs. On top of that solid structure, wound reconstruction is performed by the use of bilateral pectoralis muscle flaps followed by subcutaneous tissue and skin closure. We reported mortality rates and length of hospitalization of patients who underwent the modified sternoplasty. In total, 68 patients underwent the modified sternoplasty. Two of these critically ill patients died (2.9%). The average length of hospitalization from the diagnosis of DSWI was 24.63 ± 22.09 days. The modified sternoplasty for treating DSWI is a more complex surgery compared with other conventional sternoplasty techniques. However, this technique was demonstrated to be more effective, having a lower rate of mortality, and having a length of hospitalization lower than or comparable to other techniques previously reported in the literature.

High Mitral Annulus Calcium Score in Pre-Operative Chest Computerized Tomography and Adverse Outcomes in Mitral Valve Surgery.

BACKGROUND: Severe mitral annulus calcification (MAC) is believed to bear high operative and post-operative risk during mitral valve replacement (MVR) surgery, including longer surgery time, post-surgical valvular leaks and increased rate of embolic phenomena. We hypothesized that quantification of mitral calcium in pre-operative chest computerized tomography (CCT), performed to assess aortic root before cross-clamping may help in risk assessment of adverse intraoperative and postoperative outcomes in patients undergoing MVR. METHODS: We included patients who underwent MVR between the years 2015 and 2018 at Poriya medical center. Preoperative CCT was performed using Philips iCT 256 and Agatston mitral annulus calcium score (MACS) was retrospectively calculated using Philips Intellispace portal version 8.0. Patients were divided into MACS quintiles; 1-3 quintiles were grouped (Low MACS) and compared to the 4-5 quintiles (High MACS) group for demographic, clinical operative and post-operative parameters. RESULTS: A total of 66 patients had MVR, out of which 61% were males, with mean age of 64±9. Concomitant coronary or valvular procedures were done in 60% of patients. The median MACS was 43. High MACS (≥854) was not associated with longer bypass or cross clamp times. No differences in the MVR results were found between the groups. There were 6 post-operative embolic events; 1 mesenteric and 5 cerebral, which were not associated with MACS. CONCLUSION: MACS did not seem to be related to adverse outcomes in MVR. Due to a low event rate and probable pre-selection of patients without extreme mitral annulus calcifications our results should be confirmed in larger prospective study.

A Pilot Study of Blood Pressure Monitoring After Cardiac Surgery Using a Wearable, Non-invasive Sensor.

Background: Continuous blood pressure (BP) measurement in intensive care units is based on arterial line (AL) transducers, sometimes associated with clinical complications. Our objective was to evaluate continuous BP measurements obtained from a non-invasive, wireless photoplethysmography (PPG)-based device using two distinct configurations (wristwatch and chest-patch monitors) compared to an AL. Methods: In this prospective evaluation study, comparison of the PPG-based devices to the AL was conducted in 10 patients immediately following cardiac surgery. Pulse rate (PR), systolic BP (SBP), diastolic BP (DBP), and mean arterial pressure (MAP) were recorded using both the AL and the PPG-based devices simultaneously for an average of 432 ± 290 min starting immediately after cardiac surgery. Bland-Altman plots and Pearson's correlations were used to assess the accuracy and degree of agreement between techniques. Results: A total of ~4,000 data points were included in the final analysis. AL measurements for PR, SBP, DBP and MAP were significantly (p < 0.001) and strongly correlated with both the wristwatch (r = 0.99, r = 0.94, r = 0.93 and r = 0.96, respectively) and the chest-patch (r = 0.99, r = 0.95, r = 0.93 and r = 0.95, respectively) monitors. Both configurations showed a marginal bias of <1 mmHg for BP measurements and <1 beat/min for PR [95% limits of agreement -3,3 beat/min; BP measurements: (-6)-(-10), 6-10 mmHg] compared to AL measurements. Conclusion: The PPG-based devices offer a high level of accuracy for cardiac-related parameters compared to an AL in post-cardiac surgery patients. Such devices could provide advanced monitoring capabilities in a variety of clinical settings, including immediate post-operative and intensive care unit settings. Clinical Trial Registration:www.clinicaltrials.gov, NCT03603860.

Left atrial minimal volume: association with diastolic dysfunction and heart failure in patients in sinus rhythm or atrial fibrillation with preserved ejection fraction.

BACKGROUND: Evidence of diastolic dysfunction (DD) required for the diagnosis of heart failure with preserved ejection fraction (HFpEF) is elusive in atrial fibrillation (AF). Left ventricular (LV) and left atrial (LA) speckle-tracking echocardiography (STE) may provide rhythm independent indications of DD. We aimed to find common LV/LA myocardial mechanics parameters to demonstrate DD, using STE in patients with AF. METHODS: 176 echocardiographic assessments of patients were studied retrospectively by STE. 109 patients with history of AF were divided in three groups: sinus with normal diastolic function (n = 32, ND), sinus with DD (n = 35, DD) and patients with AF during echocardiography (n = 42). These assessments were compared to 67 normal controls. Demographic, clinical, echocardiographic and myocardial mechanic characteristics were obtained. RESULTS: The patients with DD in sinus rhythm and patients with AF were similar in age, mostly women, and had cardiovascular risk factors as well as higher dyspnea prevalence compared to either controls or patients with ND. In the AF group, LV ejection fraction (LVEF) (p = 0.008), global longitudinal strain and LA emptying were lower (p < 0.001), whereas LA volumes were larger (p < 0.001) compared to the other groups. In a multivariable analysis of patients in sinus rhythm, LA minimal volume indexed to body surface area (Vmin-I) was found to be the single significant factor associated with DD (AUC 83%). In all study patients, Vmin-I correlated with dyspnea (AUC 80%) and pulmonary hypertension (AUC 90%). CONCLUSIONS: Vmin-I may be used to identify DD and assist in the diagnosis of HFpEF in patients with AF.

Coronary artery bypass graft surgery in patients on ticagrelor therapy is not associated with adverse perioperative outcomes.

BACKGROUND: Management of patients treated with Ticagrelor is challenging, as stopping Ticagrelor prior to coronary bypass graft surgery (CABG) may increase the risk of acute stent thrombosis. The aim of the study was to compare bleeding complications in patients treated with ticagrelor combined with acetylsalicylic acid (ASA) versus ASA alone until 1 day before surgery. METHODS: Bleeding complications, defined as the composite of red blood cell transfusion ≥1000 ml, chest drainage ≥2000 ml, and bleeding requiring surgical re-exploration, were compared in 161 patients, with 101 on preoperative acetylsalicylic acid (ASA) alone (group A) and 65 on ticagrelor + ASA (group B). RESULTS: There were no differences in bleeding complications between the two groups (26% vs. 27% in group A and B, respectively), with similar chest drainage in the first 24 h (569 ± 393 ml and 649 ± 427 ml, respectively). CONCLUSIONS: Continuing ticagrelor until coronary artery bypass surgery was not associated with increased bleeding complications, suggesting that continued management with ticagrelor until surgery may be safe.

Unusual complications following left ventricular assisted device implantation: case series.

BACKGROUND: While left ventricular assisted devices (LVAD) have revolutionized the treatment of advanced heart failure, they are associated with a wide range of complications, including bleeding and infection which are the most common complications reported in the literature. Our case series report four unusual complications not related to gastrointestinal bleeding and infections and their management. CASE PRESENTATION: A 61 year old female after LVAD implantation with late onset of severe symptomatic aortic regurgitation treated by transfemoral transcatheter valve implantation (TAVI) with good long term results. A 75 year old male patient with acute pump failure secondary to cable damage, who underwent urgent pump replacement. A 49 year old female patient with a history of myoma who developed massive uterine bleeding which was treated with emergent open hysterectomy after failed gonadotropin-releasing hormone therapy replacement. A 57 year old male patient with device display failure 1 month after LVAD implantation without the ability to monitor speed, power consumption and blood flow. CONCLUSIONS: LVAD patients can be presented with a great variety of complications. Physicians should be aware of their manifestations and the management options.

Clinical, Surgical, and Sociopsychological Factors and Depression After Cardiothoracic Surgery.

BACKGROUND: Depression is highly prevalent in cardiac surgical patients and is associated with mortality. The objectives of the study were to evaluate depression scores longitudinally pre- and postoperatively and to examine the association between postoperative depression scores and clinical, surgical, and sociopsychological factors. METHODS: Depression scores were assessed using the Center for Epidemiological Study of Depression (CES-D) in 100 cardiac surgical patients who underwent cardiac surgery preoperatively, during hospitalization, and at 2 and 6 week after discharge. Clinical, surgical, and sociopsychological predictors of depression scores were recorded. RESULTS: The average depression scores significantly increased from preoperative levels (14.9 ± 1.07) to during hospitalization (21.5 ± 1.05) and decreased at both 2 weeks (15.8 ± 1.07) and 6 weeks after discharge (14.0 ± 1.06), as compared with scores during hospitalization (P < .001). The percentage of patients who scored CES-D > 16 increased significantly from preoperative (39%) to hospitalization (71%) and decreased gradually at 2 weeks (45%) and 6 weeks (37%) after discharge (P < .001). Significant predictors of high postoperative CES-D scores were female gender, ejection fraction < 50%, and high preoperative CES-D scores. CONCLUSIONS: High depression scores after cardiac surgery suggest that perioperative screening and management of depression after surgery are necessary and may improve outcomes of these patients who are at high risk for depression. Further understanding of the factors that contribute to high depression scores is required to facilitate clinical intervention.

The association between carotid calcium on dental panoramic radiographs and coronary calcium score on chest computerized tomography.

OBJECTIVES: Coronary artery calcium measured by CT predicts future coronary events. Similarly, carotid artery calcium on dental panoramic radiographs has been associated with increased cardiovascular events. Pre-procedural assessment of candidates for valve replacement in our institution includes panoramic radiographs and chest tomography. We aimed to assess the association of carotid calcium on panoramic radiographs with coronary artery calcium on chest tomography. METHODS: Paired pre-procedural panoramic radiographs and chest tomography scans were done in 177 consecutive patients between October 2016 and October 2017. Carotid calcium was quantified using NIH's ImageJ. Coronary artery calcium was quantified by the Agatston score using Philips Intellispace portal, v. 8.0.1.20640. RESULTS: Carotid calcium maximal intensity, area and perimeter were higher among patients with high coronary artery calcium. Non-zero carotid calcium was found in half of patients with high coronary artery calcium, doubling prevalence of low coronary artery calcium. CONCLUSION: Carotid calcium identified in panoramic radiographs was associated with high coronary artery calcium. Awareness of carotid calcium recognized by dental practitioners in low-cost, low radiation and commonly done panoramic radiographs may be useful to identify patients at risk of coronary disease with potential future cardiovascular events.

The impact of COVID-19 pandemic on cardiac surgery in Israel.

BACKGROUND: Ever since the coronavirus disease 2019 (COVID-19) has become a pandemic, worldwide efforts are being made to "flatten the curve". Israel was amongst the first countries to impose significant restrictions. As a result, cardiac surgeons have been required to scale down their routine practice, resulting in a significant reduction in the number of cardiac surgeries. The aim of this study is to characterize the impact of COVID-19 on cardiac surgery in Israel. METHODS: This is a retrospective observational study performed in two cardiac surgery departments in Israel and includes all patients who underwent cardiac surgery in March and April during the years 2019 and 2020. The patient cohort was divided into two groups based on the year of operation. Analysis of the patients' baseline characteristics, operative data, and postoperative outcome, was performed. RESULTS: The 2019 group (n = 173), and the 2020 group (n = 108) were similar regarding their baseline characteristics, previous medical history, and rates of previous revascularization interventions. However, compared to the 2019 group, patients in the 2020 group were found to be more symptomatic (NYHA class IV; 2.4% vs. 6.2%, p = 0.007). While all patients underwent similar procedures, patients in the 2020 group had significantly longer procedural time (p < 0.001). In-hospital mortality rate was found to be significantly higher in group 2020 (13% vs. 5.2%, p = 0.037). CONCLUSIONS: While the number of patients undergoing cardiac surgery declined during the outbreak period, the rate of surgical mortality increased. One explanation for this might be delayed hospital arrival.

Placenta-Derived Cell Therapy to Treat Patients With Respiratory Failure Due to Coronavirus Disease 2019.

OBJECTIVES: To determine whether placental cell therapy PLacental eXpanded (PLX)-PAD (Pluristem Therapeutics, Haifa, Israel) may be beneficial to treating critically ill patients suffering from acute respiratory distress syndrome due to coronavirus disease 2019. DESIGN: Retrospective case report of critically ill coronavirus disease 2019 patients treated with PLacental eXpanded (PLX)-PAD from March 26, 2020, to April 4, 2020, with follow-up through May 2, 2020. SETTING: Four hospitals in Israel (Rambam Health Care Campus, Bnai Zion Medical Center, and Samson Assuta Ashdod University Hospital), and Holy Name Medical Center in New Jersey. PATIENTS: Eight critically ill patients on invasive mechanical ventilation, suffering from acute respiratory distress syndrome due to coronavirus disease 2019. INTERVENTIONS: Intramuscular injection of PLacental eXpanded (PLX)-PAD (300 × 106 cells) given as one to two treatments. MEASUREMENTS AND MAIN RESULTS: Mortality, time to discharge, and changes in blood and respiratory variables were monitored during hospitalization to day 17 posttreatment. Of the eight patients treated (median age 55 yr, seven males and one female), five were discharged, two remained hospitalized, and one died. By day 3 postinjection, mean C-reactive protein fell 45% (240.3-131.3 mg/L; p = 0.0019) and fell to 77% by day 5 (56.0 mg/L; p < 0.0001). Pao2/Fio2 improved in 5:8 patients after 24-hour posttreatment, with similar effects 48-hour posttreatment. A decrease in positive end-expiratory pressure and increase in pH were statistically significant between days 0 and 14 (p = 0.0032 and p = 0.00072, respectively). A decrease in hemoglobin was statistically significant for days 0-5 and 0-14 (p = 0.015 and p = 0.0028, respectively), whereas for creatinine, it was statistically significant between days 0 and 14 (p = 0.032). CONCLUSIONS: Improvement in several variables such as C-reactive protein, positive end-expiratory pressure, and Pao2/Fio2 was observed following PLacental eXpanded (PLX)-PAD treatment, suggesting possible therapeutic effect. However, interpretation of the data is limited due to the small sample size, use of concomitant investigational therapies, and the uncontrolled study design. The efficacy of PLacental eXpanded (PLX)-PAD in coronavirus disease 2019 should be further evaluated in a controlled clinical trial.

Local prolonged release of antibiotic for prevention of sternal wound infections postcardiac surgery-A novel technology.

INTRODUCTION: Sternal wound infection (SWI) is a devastating postcardiac surgical complication. D-PLEX100 (D-PLEX) is a localized prolonged release compound applied as a prophylactic at the completion of surgery to prevent SWI. The D-PLEX technology platform is built as a matrix of alternating layers of polymers and lipids, entrapping an antibiotic (doxycycline). The objective of this study was to assess the safety profile and pharmacokinetics of D-PLEX in reducing SWI rates postcardiac surgery. METHOD: Eighty-one patients were enrolled in a prospective single-blind randomized controlled multicenter study. Sixty patients were treated with both D-PLEX and standard of care (SOC) and 21 with SOC alone. Both groups were followed 6 months for safety endpoints. SWI was assessed at 90 days. RESULTS: No SWI-related serious adverse events (SAEs) occurred in either group. The mean plasma Cmax in patients treated with D-PLEX was about 10 times lower than the value detected following the oral administration of doxycycline hyclate with an equivalent overall dose, and followed by a very low plasma concentration over the next 30 days. There were no sternal infections in the D-PLEX group (0/60) while there was one patient with a sternal infection in the control group (1/21, 4.8%). CONCLUSION: D-PLEX was found to be safe for use in cardiac surgery patients. By providing localized prophylactic prolonged release of broad-spectrum antibiotics, D-PLEX has the potential to prevent SWI postcardiac surgery and long-term postoperative hospitalization, reducing high-treatment costs, morbidity, and mortality.

Association Between Neurohormone Levels and Exercise Testing Measures in Patients with Mechanical Circulatory Supports.

Continuous-flow left ventricular assist device (CF-LVAD) recipients exhibit impaired exercise capacity. Long-term continuous blood flow also elevates norepinephrine (NE) and aldosterone (Aldo) levels. However, the relationship between exercise capacity and neurohormonal activation has not been elucidated. Our study objective was to assess the association between cardiopulmonary exercise testing (CPT) measures and neurohormonal levels in CF-LVAD recipients. Symptom-limited CPT on a treadmill, using the modified Bruce protocol was performed in 15 CF-LVAD recipients. Norepinephrine and Aldo levels were measured, and the association between their levels and CPT measures were assessed. Peak VO2 (13.6 ml/kg/min) and percent age, sex predicted VO2 max (49.4%), and oxygen pulse (O2 pulse) (9.0 ± 4.0 ml/beat) were low, whereas minute ventilation/carbon dioxide output (VE/VCO2) slope (35) was elevated. In addition, VO2 at anaerobic threshold (VO2 AT), and O2 pulse values negatively correlated with NE levels. Norepinephrine levels positively correlated with chronotropic responses and heart rate (HR) recovery. Aldo levels in CF-LVAD recipients were not related to any CPT measures. Continuous-flow left ventricular assist device recipients exhibited impaired exercise capacity and chronotropic incompetence (CI). Despite the association of NE levels with chronotropic responses at peak exercise, neither NE levels nor chronotropic responses predicted peak VO2. This suggests that CI may not be the primary factor responsible for the low peak VO2. O2 pulse, which is a combined measure for stroke volume and peripheral oxygen extraction during exercise, was an independent predictor of peak VO2. Future studies should examine the contribution of peripheral factors to exercise capacity limitations.

Correction to: Cardiac surgery in patients with Hemophilia:is it safe?

An amendment to this paper has been published and can be accessed via the original article.