Improved early risk stratification of deep sternal wound infection risk after coronary artery bypass grafting

BACKGROUND

Deep sternal wound infection (DSWI) following open heart surgery is associated with excessive morbidity and mortality. Contemporary DSWI risk prediction models aim at identifying high-risk patients with varying complexity and performance characteristics. We aimed to optimize the DSWI risk factor set and to identify additional risk factors for early postoperative detection of patients prone to DSWI.

METHODS

Single-centre retrospective analysis of patients with isolated multivessel coronary artery disease undergoing myocardial revascularization at Paracelsus Medical University Nuremberg between 2007 and 2022 was performed to identify risk factors for DSWI. Three data sets were created to examine preoperative, intraoperative, and early postoperative parameters, constituting the "Baseline", the "Improved Baseline" and the "Extended" models. The "Extended" data set included risk factors that had not been analysed before. Univariable and stepwise forward multiple logistic regression analyses were performed for each respective set of variables.

RESULTS

From 5221 patients, 179 (3.4%) developed DSWI. The "Extended" model performed best, with the area under the curve (AUC) of 0.80, 95%-CI: [0.76, 0.83]. Pleural effusion requiring intervention, postoperative delirium, preoperative hospital stay > 24 h, and the use of fibrin sealant were new independent predictors of DSWI in addition to age, Diabetes Mellitus on insulin, Body Mass Index, peripheral artery disease, mediastinal re-exploration, bilateral internal mammary harvesting, acute kidney injury and blood transfusions.

CONCLUSIONS

The "Extended" regression model with the short-term postoperative complications significantly improved DSWI risk discrimination after surgical revascularization. Short preoperative stay, prevention of postoperative delirium, protocols reducing the need for evacuation of effusion and restrictive use of fibrin sealant for sternal closure facilitate DSWI reduction.

TRIAL REGISTRATION

The registered retrospective study was registered at the study centre and approved by the Institutional Review Board of Paracelsus Medical University Nuremberg (IRB-2019-005).

Long-term survival after surgical treatment for post-infarction mechanical complications: results from the Caution study

BACKGROUND AND AIMS

Mechanical complications (MCs) are rare but potentially fatal sequelae of acute myocardial infarction (AMI). Surgery, though challenging, is considered the treatment of choice. The authors sought to study early and long-term results of patients undergoing surgical treatment for post-AMI MCs.

METHODS

Patients undergone surgical treatment for post-infarction MCs between 2001 through 2019 in 27 centers worldwide were retrieved from the database of CAUTION study. In-hospital and long-term mortality were the primary outcomes. Cox proportional hazards regression models were used to determine independent factors associated with overall mortality.

RESULTS

The study included 720 patients. The median age was 70.0 [62.0-77.0] years, with a male predominance (64.6%). The most common MC encountered was ventricular septal rupture (VSR) (59.4%). Cardiogenic shock was seen on presentation in 56.1% of patients. In-hospital mortality rate was 37.4%; in more than 50% of cases, the cause of death was low cardiac output syndrome (LCOS). Late mortality occurred in 133 patients, with a median follow-up of 4.4 [1.0-8.6] years. Overall survival at 1, 5 and 10 years was 54.0%, 48.1% and 41.0%, respectively. Older age (p < 0.001) and postoperative LCOS (p < 0.001) were independent predictors of overall mortality. For hospital survivors, 10-year survival was 65.7% and was significant higher for patients with VSR than those with papillary muscle rupture (long-rank P = 0.022).

CONCLUSIONS

Contemporary data from a multicenter cohort study show that surgical treatment for post-AMI MCs continues to be associated with high in-hospital mortality rates. However, long-term survival in patients surviving the immediate postoperative period is encouraging.Trial registration number: NCT03848429.

Impact of COVID-19 on incidence and outcomes of post-infarction mechanical complications in Europe

OBJECTIVES

Post-acute myocardial infarction mechanical complications (post-AMI MCs) represent rare but life-threatening conditions, including free-wall rupture, ventricular septal rupture and papillary muscle rupture. During the coronavirus disease-19 (COVID-19) pandemic, an overwhelming pressure on healthcare systems led to delayed and potentially suboptimal treatments for time-dependent conditions. As AMI-related hospitalizations decreased, limited information is available whether higher rates of post-AMI MCs and related deaths occurred in this setting. This study was aimed to assess how COVID-19 in Europe has impacted the incidence, treatment and outcome of MCs.

METHODS

The CAUTION-COVID19 study is a multicentre retrospective study collecting 175 patients with post-AMI MCs in 18 centres from 6 European countries, aimed to compare the incidence of such events, related patients' characteristics, and outcomes, between the first year of pandemic and the 2 previous years.

RESULTS

A non-significant increase in MCs was observed [odds ratio (OR) = 1.15, 95% confidence interval (CI) 0.85-1.57; P = 0.364], with stronger growth in ventricular septal rupture diagnoses (OR = 1.43, 95% CI 0.95-2.18; P = 0.090). No significant differences in treatment types and mortality were found between the 2 periods. In-hospital mortality was 50.9% and was higher for conservatively managed cases (90.9%) and lower for surgical patients (44.0%). Patients admitted during COVID-19 more frequently had late-presenting infarction (OR = 2.47, 95% CI 1.24-4.92; P = 0.010), more stable conditions (OR = 2.61, 95% CI 1.27-5.35; P = 0.009) and higher EuroSCORE II (OR = 1.04, 95% CI 1.01-1.06; P = 0.006).

CONCLUSIONS

A non-significant increase in MCs incidence occurred during the first year of COVID-19, characterized by a significantly higher rate of late-presenting infarction, stable conditions and EuroSCORE-II if compared to pre-pandemic data, without affecting treatment and mortality.

Hemoadsorption Using CytoSorb® in Patients with Infective Endocarditis: A German-Based Budget Impact Analysis

A considerable number of infective endocarditis (IE) patients require cardiac surgery with an increased risk for postoperative sepsis. Intraoperative hemoadsorption may diminish the risk of postoperative hyperinflammation with potential economic implications for intensive care unit (ICU) occupation. The present study aimed to theoretically investigate the budget impact of a reduced length of ICU stay in IE patients treated with intraoperative hemoadsorption in the German healthcare system. Data on ICU occupation were extrapolated from a retrospective study on IE patients treated with hemoadsorption. An Excel-based budget impact model was developed to simulate the patient course over the ICU stay. A base-case scenario without therapy reimbursement and a scenario with full therapy reimbursement were explored. The annual eligible German IE patient population was derived from official German Diagnostic-Related Group (DRG) volume data. One-way deterministic sensitivity analysis and multivariate analysis were performed to evaluate the uncertainty over the model results. The use of intraoperative hemoadsorption resulted in EUR 2298 being saved per patient in the base-case scenario without therapy reimbursement. The savings increased to EUR 3804 per patient in the case of full device-specific reimbursement. Deterministic and probabilistic sensitivity analyses confirmed the robustness of savings, with a probability of savings of 87% and 99% in the base-case and full reimbursement scenario, respectively. Intraoperative hemoadsorption in IE patients might have relevant economic benefits related to reduced ICU stays, resulting in improved resource use. Further evaluations in larger prospective cohorts are warranted.

Extracorporeal life support in mitral papillary muscle rupture: Outcome of multicenter study

BACKGROUND

Post-acute myocardial infarction papillary muscle rupture (post-AMI PMR) may present variable clinical scenarios and degree of emergency due to result of cardiogenic shock. Veno-arterial extracorporeal life support (V-A ECLS) has been proposed to improve extremely poor pre- or postoperative conditions. Information in this respect is scarce.

METHODS

From the CAUTION (meChanical complicAtion of acUte myocardial infarcTion: an InternatiOnal multiceNter cohort study) database (16 different Centers, data from 2001 to 2018), we extracted adult patients who were surgically treated for post-AMI PMR and underwent pre- or/and postoperative V-A ECLS support. The end-points of this study were in-hospital survival and ECLS complications.

RESULTS

From a total of 214 post-AMI PMR patients submitted to surgery, V-A ECLS was instituted in 23 (11%) patients. The median age was 61.7 years (range 46-81 years). Preoperatively, ECLS was commenced in 10 patients (43.5%), whereas intra/postoperative in the remaining 13. The most common V-A ECLS indication was post-cardiotomy shock, followed by preoperative cardiogenic shock and cardiac arrest. The median duration of V-A ECLS was 4 days. V-A ECLS complications occurred in more than half of the patients. Overall, in-hospital mortality was 39.2% (9/23), compared to 22% (42/219) for the non-ECLS group.

CONCLUSIONS

In post-AMI PMR patients, V-A ECLS was used in almost 10% of the patients either to promote bridge to surgery or as postoperative support. Further investigations are required to better evaluate a potential for increased use and its effects of V-A ECLS in such a context based on the still high perioperative mortality.

Impact of prophylactic intra-aortic balloon pump on early outcomes in patients with severe left ventricular dysfunction undergoing elective coronary artery bypass grafting with cardiopulmonary bypass

OBJECTIVE

Our aim was to analyse whether prophylactic preoperative intraaortic balloon pump (IABP) improves outcomes in hemodynamically stable patients with low left ventricular ejection fraction (LVEF ≤30%) undergoing elective myocardial revascularization (CABG) using cardiopulmonary bypass (CPB). Secondary aim was to identify the predictors for low cardiac output syndrome (LCOS).

METHODS

Prospectively collected data of 207 consecutive patients with LVEF ≤30% undergoing elective isolated CABG with CPB from 01/2009 to 12/2019, 136 with and 71 patients without IABP, were retrieved retrospectively. Patients with prophylactic IABP were matched 1:1 with patients without IABP by a propensity score matching. Stepwise logistic regression was conducted to identify predictors of postoperative LCOS in the propensity-matched cohort. P value ≤0.05 was considered significant.

RESULTS

Reduced postoperative LCOS (9.9% vs. 26.8%, P = 0.017) was observed in patients receiving prophylactic IABP. Stepwise logistic regression identified preoperative IABP as preventive factor for postoperative LCOS [Odds Ratio (OR) 0.19,95% Confidence Interval (CI), 0.06-0.55, P = 0.004]. The need of vasoactive and inotropic support was lower in patients with prophylactic IABP at 24, 48 and 72 h after surgery (12.3 [8.2-18.6] vs. 22.2 [14.4-28.8], P < 0.001, 7.7 [3.3-12.3] vs.16.3 [8.9-27.8], P < 0.001 and 2.4 [0-7] vs. 11.5 [3.1-26], P < 0.001, respectively). The patients in both groups did not differ in terms of in-hospital mortality (7.0% vs. 9.9%, P = 0.763). There were no major IABP-related complications.

CONCLUSIONS

Elective patients with left ventricular ejection fraction ≤30% undergoing CABG with CPB and prophylactic IABP insertion had less low cardiac output syndrome and similar in-hospital mortality.

Effect of intraoperative haemoadsorption therapy on cardiac surgery for active infective endocarditis with confirmed Staphylococcus aureus bacteraemia

OBJECTIVES

Sepsis caused by infective endocarditis (IE), due to Staphylococcus aureus, is associated with significant morbidity and mortality. Blood purification using haemoadsorption (HA) may attenuate the inflammatory response. We investigated the effect of intraoperative HA on postoperative outcomes in S. aureus IE.

METHODS

Patients with confirmed S. aureus IE undergoing cardiac surgery were included in a dual-centre study between January 2015 and March 2022. Patients treated with intraoperative HA (HA group) were compared to patients not treated with HA (control group). The primary outcome was vasoactive-inotropic score within the first 72 h postoperatively and secondary outcomes were sepsis-related mortality (SEPSIS-3 definition) and overall mortality at 30 and 90 days.

RESULTS

No differences in baseline characteristics were observed between groups (haemoadsorption group, n = 75, control group, n = 55). Significantly decreased vasoactive-inotropic score was observed in the haemoadsorption group at all time points [6 h: 6.0 (0-17) vs 17 (3-47), P = 0.0014; 12 h: 2 (0-8.3) vs 5.9 (0-37), P = 0.0138; 24 h: 0 (0-5) vs 4.9 (0-23), P = 0.0064; 48 h: 0 (0-2.1) vs 0.1 (0-13), P = 0.0192; 72 h: 0 (0) vs 0 (0-5), P = 0.0014]. Importantly, sepsis-related mortality (8.0% vs 22.8%, P = 0.02) and 30-day (17.3% vs 32.7%, P = 0.03) and 90-day overall mortality (21.3% vs 40%, P = 0.03) were also significantly lower with haemoadsorption.

CONCLUSIONS

Intraoperative HA during cardiac surgery for S. aureus IE was associated with significantly lower postoperative vasopressor and inotropic requirements and resulted in lower sepsis-related and overall 30- and 90-day mortality. In this high-risk population, improved postoperative haemodynamic stabilization by intraoperative HA appears to improve survival and should be further tested in future randomized trials.

Single-Centre Retrospective Evaluation of Intraoperative Hemoadsorption in Left-Sided Acute Infective Endocarditis

Background: Cardiac surgery in patients with infective endocarditis (IE) is still associated with high mortality and morbidity; an already present inflammation might further be aggravated due to a cardiopulmonary bypass-induced dysregulated immune response. Intraoperative hemoadsorption therapy may attenuate this septic response. Our objective was therefore to assess the efficacy of intraoperative hemoadsorption in active left-sided native- and prosthetic infective endocarditis. Methods: Consecutive high-risk patients with active left-sided infective endocarditis were enrolled between January 2015 and April 2021. Patients with intraoperative hemoadsorption (Cytosorbents, Princeton, NJ, USA) were compared to patients without hemoadsorption (control). Endpoints were the incidence of postoperative sepsis, sepsis-associated death and in-hospital mortality. Predictors for sepsis-associated mortality and in-hospital mortality were analysed by multivariable logistic regression. Results: A total of 202 patients were included, 135 with active left-sided native and 67 with prosthetic valve infective endocarditis. Ninety-nine patients received intraoperative hemoadsorption and 103 patients did not. Ninety-nine propensity-matched pairs were selected for final analyses. Postoperative sepsis and sepsis-related mortality was reduced in the hemoadsorption group (22.2% vs. 39.4%, p = 0.014 and 8.1% vs. 22.2%, p = 0.01, respectively). In-hospital mortality tended to be lower in the hemoadsorption group (14.1% vs. 26.3%, p = 0.052). Key predictors for sepsis-associated mortality and in-hospital mortality were preoperative inotropic support, lactate-levels 24 h after surgery, C-reactive protein levels on postoperative day 1, chest tube output, cumulative inotropes and white blood cell counts on postoperative day 2, and new onset of dialysis. Multivariate regression analysis revealed intraoperative hemoadsorption to be associated with lower sepsis-associated (OR 0.09, 95% CI 0.013–0.62, p = 0.014) as well as in-hospital mortality (OR 0.069, 95% CI 0.006–0.795, p = 0.032). Conclusions: Intraoperative hemoadsorption holds promise to reduce sepsis and sepsis-associated mortality after cardiac surgery for active left-sided native and prosthetic valve infective endocarditis.

Enhanced Detection of Cardiac Surgery-Associated Acute Kidney Injury by a Composite Biomarker Panel in Patients with Normal Preoperative Kidney Function

We have recently shown that minor subclinical creatinine dynamic changes enable the excellent detection of acute kidney injury (AKI) within 6–12 h after cardiac surgery. The aim of the present study was to examine a combination of neutrophil gelatinase-associated lipocalin (NGAL), cystatin C (CysC) and creatinine for enhanced AKI detection early after cardiac surgery. Elective patients with normal renal function undergoing cardiac surgery using cardiopulmonary bypass were enrolled. Concentrations of plasma NGAL, serum CysC and serum creatinine were determined after the induction of general anesthesia, at the termination of the cardiopulmonary bypass and 2 h thereafter. Out of 119 enrolled patients, 51 (43%) developed AKI. A model utilizing an NGAL, CysC and creatinine triple biomarker panel including sequential relative changes provides a better prediction of cardiac surgery-associated acute kidney injury than any biomarker alone already 2 h after the termination of the cardiopulmonary bypass. The area under the receiver-operator curve was 0.77, sensitivity 77% and specificity 68%.

Artificial intelligence-based early detection of acute kidney injury after cardiac surgery

OBJECTIVES

This study aims to improve early detection of cardiac surgery-associated acute kidney injury using artificial intelligence-based algorithms.

METHODS

Data from consecutive patients undergoing cardiac surgery between 2008 and 2018 in our institution served as the source for artificial intelligence-based modeling. Cardiac surgery-associated acute kidney injury was defined according to the Kidney Disease Improving Global Outcomes criteria. Different machine learning algorithms were trained and validated to detect cardiac surgery-associated acute kidney injury within 12 hours after surgery. Demographic characteristics, comorbidities, preoperative cardiac status, intra- and postoperative variables including creatinine and hemoglobin values were retrieved for analysis.

RESULTS

From 7507 patients analyzed, 1699 patients (22.6%) developed cardiac surgery-associated acute kidney injury. The ultimate detection model, 'Detect-A(K)I', recognizes cardiac surgery-associated acute kidney injury within 12 hours with an area under the curve of 88.0%, sensitivity of 78.0%, specificity of 78.9%, and accuracy of 82.1%. The optimal parameter set includes serial changes of creatinine and hemoglobin, operative emergency, bleeding-associated variables, cardiac ischaemic time and cardiac function-associated variables, age, diuretics and active infection, chronic obstructive lung and peripheral vascular disease.

CONCLUSIONS

The 'Detect-A(K)I' model successfully detects cardiac surgery-associated acute kidney injury within 12 hours after surgery with the best discriminatory characteristics reported so far.

Nonlinear Heart Rate Variability in Patients with Chronic Obstructive Pulmonary Disease and Changes after 4-week Comprehensive Inpatient Pulmonary Rehabilitation

Cardiovascular disease is among the leading causes of mortality in chronic obstructive pulmonary disease (COPD). Nonlinear heart rate variability (NHRV) measures are markers and predictors of cardiovascular disease, particularly arrhythmias. Our aim was to investigate NHRV in patients with COPD and changes after pulmonary rehabilitation. 20-minute ECGs were used to compare NHRV (a) in 45 healthy individuals and 31 patients with COPD and (b) in 16 patients who completed rehabilitation versus 13 age- and sex-matched control patients. We studied detrended fluctuation analysis (DFA1, DFA2), fractal dimension (low, high, average FD) and sample entropy. Compared to healthy individuals, patients with COPD had lower DFA1 (p=.038). During rehabilitation high FD decreased (p=.018) and DFA2 increased (p=.043). Cluster analysis displayed an increase of DFA1 in the rehabilitation cluster with DFA1 values below 1 (p=.032). NHRV reflects altered autonomic regulation in patients with COPD. Reduced DFA1 in patients with COPD implies a stronger pro-arrhythmic substrate and altered parasympathetic modulation.

Postoperative transverse sternal nonunion with a chest wall defect managed by a tibial locking plate and a Gore-Tex dual mesh membrane: a case report

Background

Transverse sternal nonunion is a rare but disabling complication of chest trauma or a transverse sternotomy. Fixation methods, mainly used to manage the more common longitudinal sternal nonunion, often fail, leaving the surgical treatment of transverse nonunion to be a challenge.

Case presentation

We present a case of a highly-disabling, postoperative chest wall defect resulting from transverse sternal nonunion after a transverse thoracosternotomy (clamshell incision) and a concomitant rib resection. Following unsuccessful surgical attempts, the sternal nonunion was fixed with a tibial locking plate and bone grafted, while the post-rib resection chest defect was reconstructed with a Gore-Tex dual mesh membrane. Adequate chest stability was achieved, enabling complete healing of the sternal nonunion and the patient’s complete recovery.

Conclusion

We believe it is important to address both in the rare case of combined postoperative transverse sternal nonunion and the chest wall defect after rib resection. A good outcome was achieved in our patient by fixing the nonunion with an appropriately sized and shaped locking plate with bone grafting and covering the chest defect with a dual mesh membrane.

Surgical treatment for post-infarction papillary muscle rupture: a multicentre study

OBJECTIVES

Papillary muscle rupture (PMR) is a rare but potentially fatal complication of acute myocardial infarction. The aim of this study was to analyse the patient characteristics and early outcomes of the surgical management of post-infarction PMR from an international multicentre registry.

METHODS

Patients underwent surgery for post-infarction PMR between 2001 through 2019 were retrieved from database of the CAUTION study. The primary end point was in-hospital mortality.

RESULTS

A total of 214 patients were included with a mean age of 66.9 (standard deviation: 10.5) years. The posteromedial papillary muscle was the most frequent rupture location (71.9%); the rupture was complete in 67.3% of patients. Mitral valve replacement was performed in 82.7% of cases. One hundred twenty-two patients (57%) had concomitant coronary artery bypass grafting. In-hospital mortality was 24.8%. Temporal trends revealed no apparent improvement in in-hospital mortality during the study period. Multivariable analysis showed that preoperative chronic kidney disfunction [odds ratio (OR): 2.62, 95% confidence interval (CI): 1.07-6.45, P = 0.036], cardiac arrest (OR: 3.99, 95% CI: 1.02-15.61, P = 0.046) and cardiopulmonary bypass duration (OR: 1.01, 95% CI: 1.00-1.02, P = 0.04) were independently associated with an increased risk of in-hospital death, whereas concomitant coronary artery bypass grafting was identified as an independent predictor of early survival (OR: 0.38, 95% CI: 0.16-0.92, P = 0.031).

CONCLUSIONS

Surgical treatment for post-infarction PMR carries a high in-hospital mortality rate, which did not improve during the study period. Because concomitant coronary artery bypass grafting confers a survival benefit, this additional procedure should be performed, whenever possible, in an attempt to improve the outcome.

CLINICAL TRIAL REGISTRATION

clinicaltrials.gov: NCT03848429.

Surgical Treatment of Postinfarction Ventricular Septal Rupture

IMPORTANCE

Ventricular septal rupture (VSR) is a rare but life-threatening mechanical complication of acute myocardial infarction associated with high mortality despite prompt treatment. Surgery represents the standard of care; however, only small single-center series or national registries are usually available in literature, whereas international multicenter investigations have been poorly carried out, therefore limiting the evidence on this topic.

OBJECTIVES

To assess the clinical characteristics and early outcomes for patients who received surgery for postinfarction VSR and to identify factors independently associated with mortality.

DESIGN, SETTING, AND PARTICIPANTS

The Mechanical Complications of Acute Myocardial Infarction: an International Multicenter Cohort (CAUTION) Study is a retrospective multicenter international cohort study that includes patients who were treated surgically for mechanical complications of acute myocardial infarction. The study was conducted from January 2001 to December 2019 at 26 different centers worldwide among 475 consecutive patients who underwent surgery for postinfarction VSR.

EXPOSURES

Surgical treatment of postinfarction VSR, independent of the technique, alone or combined with other procedures (eg, coronary artery bypass grafting).

MAIN OUTCOMES AND MEASURES

The primary outcome was early mortality; secondary outcomes were postoperative complications.

RESULTS

Of the 475 patients included in the study, 290 (61.1%) were men, with a mean (SD) age of 68.5 (10.1) years. Cardiogenic shock was present in 213 patients (44.8%). Emergent or salvage surgery was performed in 212 cases (44.6%). The early mortality rate was 40.4% (192 patients), and it did not improve during the nearly 20 years considered for the study (median [IQR] yearly mortality, 41.7% [32.6%-50.0%]). Low cardiac output syndrome and multiorgan failure were the most common causes of death (low cardiac output syndrome, 70 [36.5%]; multiorgan failure, 53 [27.6%]). Recurrent VSR occurred in 59 participants (12.4%) but was not associated with mortality. Cardiogenic shock (survived: 95 [33.6%]; died, 118 [61.5%]; P < .001) and early surgery (time to surgery ≥7 days, survived: 105 [57.4%]; died, 47 [35.1%]; P < .001) were associated with lower survival. At multivariate analysis, older age (odds ratio [OR], 1.05; 95% CI, 1.02-1.08; P = .001), preoperative cardiac arrest (OR, 2.71; 95% CI, 1.18-6.27; P = .02) and percutaneous revascularization (OR, 1.63; 95% CI, 1.003-2.65; P = .048), and postoperative need for intra-aortic balloon pump (OR, 2.98; 95% CI, 1.46-6.09; P = .003) and extracorporeal membrane oxygenation (OR, 3.19; 95% CI, 1.30-7.38; P = .01) were independently associated with mortality.

CONCLUSIONS AND RELEVANCE

In this study, surgical repair of postinfarction VSR was associated with a high risk of early mortality; this risk has remained unchanged during the last 2 decades. Delayed surgery seemed associated with better survival. Age, preoperative cardiac arrest and percutaneous revascularization, and postoperative need for intra-aortic balloon pump and extracorporeal membrane oxygenation were independently associated with early mortality. Further prospective studies addressing preoperative and perioperative patient management are warranted to hopefully improve the currently suboptimal outcome.

Surgical Treatment of Post-Infarction Left Ventricular Free-Wall Rupture: A Multicenter Study

BACKGROUND

Left ventricular free-wall rupture (LVFWR) is an uncommon but serious mechanical complication of acute myocardial infarction. Surgical repair, though challenging, is the only definitive treatment. Given the rarity of this condition, however, results after surgery are still not well established. The aim of this study was to review a multicenter experience with the surgical management of post-infarction LVFWR and analyze the associated early outcomes.

METHODS

Using the CAUTION (Mechanical Complications of Acute Myocardial Infarction: an International Multicenter Cohort Study) database, we identified 140 patients who were surgically treated for post-acute myocardial infarction LVFWR in 15 different centers from 2001 to 2018. The main outcome measured was operative mortality. Multivariate analysis was carried out by constructing a logistic regression model to identify predictors of postoperative mortality.

RESULTS

The mean age of patients was 69.4 years. The oozing type of LVFWR was observed in 79 patients (56.4%), and the blowout type in 61 (43.6%). Sutured repair was used in the 61.4% of cases. The operative mortality rate was 36.4%. Low cardiac output syndrome was the main cause of perioperative death. Myocardial rerupture after surgery occurred in 10 patients (7.1%). Multivariable analysis revealed that preoperative left ventricular ejection fraction (P < .001), cardiac arrest at presentation (P = .011), female sex (P = .044), and the need for preoperative extracorporeal life support (P = .003) were independent predictors for operative mortality.

CONCLUSIONS

Surgical repair of post-infarction LVFWR carries a high operative mortality. Female sex, preoperative left ventricular ejection fraction, cardiac arrest, and extracorporeal life support are predictors of early mortality.

Ventricular arrhythmic disturbances and autonomic modulation after beating-heart revascularization in patients with pulmonary normotension

BACKGROUND

De-novo ventricular arrhythmias are potentially life-threatening complications after beating-heart revascularization (off-pump CABG). Whether pulmonary hypertension can influence initiation of ventricular arrhythmias through increased sympathetic activity is controversial. In order to determine the influence of pulmonary hypertension on its relative contribution to ventricular arrhythmia, we first had to define the role of cardiac autonomic modulation in patients with pulmonary normotension. We aimed to observe how parameters of linear and nonlinear heart rate variability are changed pre- and postoperatively in patients with pulmonary normotension undergoing off-pump CABG.

METHODS

Fifteen-minute ECG recordings were collected before and after off-pump CABG in 54 patients with multivessel coronary artery disease and pulmonary normotension to determine linear (TP, HF, LF, LF:HF ratio) and nonlinear detrended fluctuation analysis (alpha1, alpha2) and fractal dimension (average, high and low) parameters of heart rate variability. Arrhythmia was monitored preoperatively in 24-hour Holter recordings and postoperatively by continuous monitoring and clinical assessment.

RESULTS

Deterioration from simple (Lown I-II) to complex (Lown III-V) ventricular arrhythmia was observed in 19 patients, and improvement from complex to simple arrhythmia in five patients (P = 0.022). Patients with postoperative deterioration of ventricular arrhythmia had preoperatively significantly lower values of TP, HF and LF (P = 0.024-0.043) and postoperatively significantly higher values on the low fractal dimension index (P = 0.031) than patients with postoperative improvement of arrhythmia.

CONCLUSION

Patients experiencing postoperative deterioration of ventricular arrhythmia already have impaired autonomic regulation before surgery. Higher postoperative values on the low fractal dimension index indicate that sympathetic predominance with or without concomitant vagal withdrawal is the underlying neurogenic mechanism contributing to ventricular arrhythmia.

Assessment of nonlinear heart rate dynamics after beating-heart revascularization

BACKGROUND

Advanced nonlinear methods of measuring heart rate variability (HRV) derived from the mathematics of complex dynamics and fractal geometry have provided new insights into the abnormalities of heart rate behavior in various pathologic conditions. These methods have provided additional prognostic information compared with traditional HRV measures and clearly have complemented the conventional linear methods. Knowledge about the behavior of complex cardiac dynamics indices after different cardiac procedures is very limited, however. We aimed to clarify how nonlinear heart rate dynamics are affected by beating-heart revascularization (off-pump coronary artery bypass graft [CABG] surgery) within the first week after the procedure.

METHODS

Included in the study were 66 patients who had isolated stable multivessel coronary artery disease and were in normal sinus rhythm. The patients were on chronic beta-blocker therapy and were scheduled for off-pump CABG. We performed 15-minute high-resolution electrocardiographic recordings preoperatively and on the third and seventh postoperative days to assess linear and nonlinear heart rate dynamics. Frequency-domain measurements, detrended fluctuation analysis (DFA) with short-term (<or=11 beats, alpha1) and long-term (>11 beats, alpha2) correlation properties of RR-intervals, and fractal dimension (FD) measurements (average, high, and low) were made. Arrhythmia was monitored preoperatively with 24-hour Holter recordings, postoperatively by continuous monitoring for the first 4 days after the procedure, and subsequently by clinical monitoring; 24-hour Holter recordings were obtained again on the seventh postoperative day. We used the paired-samples Student t test, the Mann-Whitney U test, and the Fisher exact test for statistical analyses. Differences in arrhythmia occurrence before and after the procedure were tested with the Wilcoxon signed rank test and the McNemar test. A P level < .05 was considered statistically significant.

RESULTS

Values for all frequency-domain parameters decreased significantly after off-pump CABG (P< .001). Values for the alpha1 and high FD parameters decreased significantly after the procedure (P= .028 and .001, respectively), whereas alpha2 increased significantly (P= .023). DFA alpha1 was significantly lower in patients with postoperative atrial fibrillation than in patients remaining in sinus rhythm (mean +/- SD, 0.79+/-0.32 versus 1.13+/-0.45 [P= .003] on the third postoperative day; 0.89+/-0.31 versus 1.22+/-0.34 [P< .001] on the seventh postoperative day), whereas low and average FDs were significantly higher (1.84+/-0.16 versus 1.68+/-0.19 [P= .003] on the third postoperative day and 1.77+/-0.18 versus 1.66+/-0.17 [P= .01] on the seventh postoperative day for the low FD; 1.83+/-0.09 versus 1.76+/-0.10 [P= .011] on the third postoperative day and 1.80+/-0.11 versus 1.73+/-0.10 [P= .014] on the seventh postoperative day for the average FD). The low FD was significantly higher on the third postoperative day in patients with postoperative deterioration of ventricular ectopy than in patients with improved ventricular ectopy (1.74+/-0.17 versus 1.48+/-0.08, [P= .03]).

CONCLUSION

The decreases in alpha1, average FD, and high FD indicate that a profound decay of cardiac complexity and fractal correlation can be observed after off-pump CABG. Furthermore, a more extensive impairment of nonlinear indices was observed in patients who developed postoperative arrhythmias than in those who remained in stable sinus rhythm. Our findings suggest that the postoperative hyperadrenergic setting acts as a preliminary condition in which both reduced and enhanced vagal activity may predispose patients to arrhythmia, indicating that postoperative rhythm disturbances are an end point associated with divergent autonomic substrates.

The Preferable Use of Port Access Surgical Technique for Right and Left Atrial Procedures

A 31-year-old woman who had undergone aortic and mitral valve replacement 1 year previously was hospitalized with suspected prosthetic valve endocarditis. Freestyle stentless aortic xenograft was successfully replaced using freestanding total aortic root replacement techniques at the left ventricular outflow tract position, and aorta-to-right coronary artery bypass was also applied with a saphenous vein graft. The patient developed multiple systemic problems during the preoperative and postoperative periods and was successfully treated with intensive interventions. She was discharged at the postoperative fourth month, and the following 28 months were uneventful.

Imaging of power spectral heart rate variability regarding subject position

Heart rate variability (HRV) and its assessment using power spectral analysis revealed a possibility to quantify the characteristics of autonomic nervous system, related cardiovascular status and sympathovagal interaction. This study was designed to assess vagal tone in supine and right recumbent position in normal healthy subjects as many maneuvers that potentially increase vagal tone have been sought both in normal subjects and in patients with heart disease. Seven subjects, four male and three female, aged 20-27 years were enrolled in the study. To evaluate the time-dependent stability of short term ECG recordings, every subject participated in six ECG recording sessions (three successive morning and three successive afternoon measurements). Heart rate power spectra were obtained by off-line Fast Fourier Transform analysis. The frequency domain measures, namely very low frequency power (VLF), low frequency power (LF), high frequency power (HF) and total power were determined, and their normalized correlates used in the comparison between supine and right recumbent position. Normalized high frequency (nHF) indicated cardiac vagal activity, normalized low frequency power indexed sympathetic modulated activity, low frequency power/high frequency power ratio (LF/HF) represented sympathovagal balance. The results showed remarkable variation among successive day measurements as well as among study subjects. However, several types of response to adopting right recumbent position could be identified. In the first, in right recumbent position the values of nHF, indicator of vagal activity did not differ appreciably from the values measured in supine position. Secondly, there was a tendency towards higher nHF values and lower LF/HF power ratio in supine position. We were not able to notice any appreciable difference among morning and afternoon short-term measurements. Finally, our results do not suggest higher vagal modulation when lying in right recumbent position.