Prevalence, clinical characteristics and outcomes of high-risk patients treated for severe aortic stenosis prior to and after transcatheter aortic valve implantation availability.

OBJECTIVES: Transcatheter aortic valve implantation (TAVI) has emerged as an effective treatment for high-risk patients with severe aortic stenosis (AS). The aim of our study was to compare the prevalence, characteristics and outcomes of high-risk patients treated prior to and after the availability of TAVI in our high-volume surgical institution. METHODS: Among 879 consecutive patients treated 2 years before ('pre-TAVI era') and after ('modern era') the availability of TAVI in our institution, 83 patients were at high risk [defined by logistic European System for Cardiac Operative Risk Evaluation (EuroSCORE) >20%]. RESULTS: Among all patients treated for severe AS, the prevalence of high-risk patients was higher in the modern era (12.7 vs 4.9%, P < 0.0001). In the modern era, high-risk patients were treated by TAVI in 89% of cases. Despite similar logistic EuroSCORE (34.9 vs 34%, P = 0.96), the clinical characteristics of these patients have evolved: high-risk patients in the modern era were older (85.3 ± 5.9 vs 78.5 ± 6.5 years, P = 0.0005) and presented more frequently with New York Heart Association class III-IV (92.3 vs 61.1%, P = 0.003), while high-risk patients treated by surgical aortic valve replacement in the pre-TAVI era presented more frequently with a critical preoperative status (33.3 vs 7.7%, P = 0.01), lower left ventricular ejection fraction (41 ± 14 vs 49 ± 15%, P = 0.05) and a history of recent myocardial infarction (27.8 vs 6.1%, P = 0.02). The overall 1-year survival was not different for high-risk patients treated in the pre-TAVI era or in the modern era (61 ± 11 vs 68 ± 6%, P = 0.52). CONCLUSIONS: The availability of TAVI has increased the prevalence of high-risk patients treated for severe AS and changed the clinical features of this kind of patients who were rarely surgically treated before. The 1-year survival was similar between pre-TAVI and modern eras.

Apical left ventricular false aneurysm after transapical transcatheter aortic valve implantation.

Transcatheter valve implantation (TAVI) is becoming a routine procedure to treat severe symptomatic aortic stenosis. It is associated with complications different from those of conventional aortic valve surgery. We describe an 80-year old man who developed an apical left ventricular (LV) false aneurysm 3 months after transapical TAVI (TA-TAVI) complicated postoperatively by a surgical site infection (SSI). Three months earlier, an Edwards Sapien bioprosthesis no. 29 had been successfully inserted transapically because of severe comorbidities and a very large aortic annulus. His postoperative course was complicated by acute respiratory failure, gastrointestinal bleeding and a surgical site infection of the thoracic incision; Escherichia coli and Klebsiella pneumonia were isolated. After surgical debridement drainage and prolonged antibiotic therapy, the wound healed correctly. His emergency chest computed tomography upon readmission for the acute onset of a beating tumefaction at the TA-TAVI site showed a false aneurysm of the LV apex. The apex was closed directly during emergency surgery. The postoperative course was uneventful. Surgical site infection after TA-TAVI, its frequency, treatment and potential role as an underlying cause of this severe complication are discussed.

Evaluation of blind nasotracheal suctioning and non-bronchoscopic mini-bronchoalveolar lavage in critically ill patients with infectious pneumonia: a preliminary study.

BACKGROUND: We evaluated the diagnostic performance and safety of combined blind nasotracheal suctioning and non-bronchoscopic mini-bronchoalveolar lavage (mini-BAL) to obtain respiratory secretion specimens from spontaneously breathing, non-intubated patients with infectious pneumonia in intensive care. METHODS: Patients suspected of having infectious pneumonia were included prospectively. Three samples were obtained: expectorated sputum, nasotracheal suctioning, and mini-BAL via a double telescopic catheter (Combicath). Under local anesthesia, nasotracheal suctioning was done according to standard recommendations. Then mini-BAL was performed; the bronchial catheter serves as a guide for the mini-BAL catheter, and tracheal position is verified via colorimetric capnography. RESULTS: We included 36 subjects (29 men, median age 69 y, median Simplified Acute Physiology Score II 32), of which 32 (89%) underwent nasotracheal suctioning and mini-BAL, and from 13 (36%) we collected expectorated sputum. Based on colorimetric capnography confirmation of the tracheal position, 75% (24/32) of the successful combined procedures were achieved on the first attempt. The median duration of the combined procedure was 7 min. Bacterial pneumonia was diagnosed in 24/36 (67%) subjects, among whom 21 (88%) had undergone successful nasotracheal suctioning and mini-BAL, respectively, for 8/21 (38% [95% CI 0.17-0.58%] and 14/21 (67% [95% CI 0.46-0.86%]). Mini-BAL diagnosed a significantly higher percentage of bacterial pneumonias than did nasotracheal suctioning. Expectorated sputum yielded no diagnoses. CONCLUSIONS: Blind nasotracheal suctioning confirmed via colorimetric capnography allows microbiological diagnosis, and can be enhanced by non-bronchoscopic mini-BAL. Colorimetric capnography helps confirm bronchial tube position. Non-bronchoscopic mini-BAL is a novel and feasible way to collect bronchial secretions without fibroscopy. (ClinicalTrials.gov NCT00763620.).

Septic rupture of an atherosclerotic plaque of the ascending aorta.

Infectious aortitis has become a rare disease thanks to the widespread use of antibiotics. We report the case of a patient who, 15 days after initiation of antibiotics for bacteraemia due to methicillin-resistant Staphylococcus aureus (MRSA), developed acute chest pain followed by haemodynamic instability. A tamponade due to a rupture into the pericardium of the ascending aorta at the site of an atherosclerotic plaque was diagnosed by an emergent chest contrasted computed tomography (CT). Intraoperatively, the septic nature of the rupture was suspected. All aortic atherosclerotic plaque samples grew MRSA. Postoperatively, the patient had an uneventful recovery after 12 weeks of antibiotic therapy. Transoesophageal echocardiography and chest CT were normal at 3 months after cessation of antibiotics. This case report permits the review of some characteristics of this disease, its physiopathology as well as the therapeutic implications.

An unusual cause of acute abdominal pain after cardiac surgery: acute epiploic appendagitis.

Abdominal complications following cardiac surgery remain unusual, but are associated with high mortality. The most common abdominal surgical complications are mesenteric ischaemia, diverticulitis, pancreatitis, gastrointestinal bleeding and cholecystitis. We describe a case of a 73-year old woman with acute abdominal pain mimicking cholecystitis on day 10 after aortic valve replacement. An abdominal examination showed tenderness of the right upper quadrant with Murphy's sign. Complete blood count, blood chemistries and urinalysis were normal as were the abdominal and chest X-rays and abdominal ultrasonography. The abdominal computed-tomography (CT) scan enabled us to rule out cholecystitis, as it demonstrated the typical appearance of epiploic appendagitis on the right colon, 1 cm below the gallbladder. Epiploic appendagitis results from twisting, kinking or venous thrombosis of an epiploic appendage. Depending on its localization, it mimics many diagnoses requiring surgery: colitis, diverticulitis, appendicitis and cholecystitis. An abdominal CT scan is the diagnostic imaging tool of choice. All physicians involved in post-cardiac surgery care should be aware of this self-limiting disease that usually resolves with non-steroidal anti-inflammatory drugs and watchful waiting, and to avoid unnecessary surgery because the spontaneous evolution of epiploic appendagitis is usually benign.

Preoperative carriage and postoperative same-species sternal wound infection after cardiac surgery.

Sternal wound infection (SWI) after cardiac surgery remains an important problem. Prediction of pathogens involved in such infection could guide antibiotics. From April 1, 2006 to December 31, 2008, retrospectively, we evaluated the diagnostic value of preoperative methicillin-sensible Staphylococcus aureus (MSSA), methicillin-resistant S. aureus (MRSA) or multi-drug resistant Gram-negative bacillus (MDRGNB) carriage to predict same-pathogens involved in postoperative SWI. All patients referred for elective cardiac surgery were screened using multisite (nares, axillae, rectal) sampling at admission to detect MSSA, MRSA, and MDRGNB. Of the 1895 patients addressed, 425 patients (22.4%) were colonized at admission. Preoperative carriers more frequently developed SWI than non-carriers, respectively, 11% vs. 5.5% (P<0.05). Because of the small sample, MDRGNB carriers could not be analyzed. For prediction of MSSA SWI with preoperative MSSA carriage, the area under the receiver operating characteristic (ROC) curve was 0.720 (95% confidence interval (CI), 0.364-0.796) and 0.710 (95% CI, 0.623-0.787) for prediction of MRSA SWI with preoperative MRSA carriage. Preoperative MSSA carriage is frequent but preoperative MRSA or MDRGNB carriage remains infrequent. The ability of preoperative carriage to predict a same-pathogen-postoperative SWI was low and should not be used to guide empirical antibiotherapy.

Frailty after aortic valve replacement (AVR) in octogenarians.

In order to analyze the quality of life (QoL) or frailty after AVR for octogenarians, we studied 84 patients older than 80 years who underwent aortic valve replacement alone or in combination with coronary artery bypass, between April 1998 and December 2001. Follow-up was performed in May 2002 with a telephonic interview to evaluate the self-rated QoL, health, and three frailty markers: falls, activity of daily living (ADL) and mood disorder. In-hospital mortality was 16.7%. Fourteen deaths occurred during the follow-up: survival estimates were 85.5% at 1 year and 68.6% at 3 years. Forty-one patients (73.2%) were in New York Heart Association (NYHA) classes I-II for dyspnea and 42 patients (75.0%) were free of angina. Fifty-one patients (91.1%) lived in their own homes. Forty-eight (85.7%) had at least one frailty marker: falls (26.8%), loss of autonomy for ADL (27.0%) or suspected depression (20.2%). All frailty markers were associated with self-rated QoL but not with self-rated health. AVR for octogenarians is associated with good outcome but this population is frail and further studies should assess the usefulness of pre- and postoperative geriatric approach.

Prone positioning and acute respiratory distress syndrome after cardiac surgery: a feasibility study.

OBJECTIVE: To determine the feasibility, safety, and efficacy on PaO(2)/F(I)O(2) ratio of prone positioning (PP) for acute respiratory distress syndrome (ARDS) after cardiac surgery. DESIGN: Retrospective review of information entered prospectively in the authors' database. SETTING: A private community nonteaching hospital. PARTICIPANTS: Sixteen patients who developed ARDS after cardiac surgery from January 2004 through June 2005. INTERVENTIONS: PP to improve oxygenation. MEASUREMENTS AND MAIN RESULTS: After a median duration of 18 (range, 14-27) hours in PP, PaO(2)/F(I)O(2) improved in 14 (87.5%) patients. For the entire population, median PaO(2)/F(I)O(2) rose from 87 (range, 56-161) before PP to 194 (range, 94-460; p < 0.05) after it. After supine repositioning (SR), PaO(2)/F(I)O(2) declined to 146 (range, 72-320; not significant). PaO(2)/F(I)O(2) at the end of PP and 1 day after SR were comparable, respectively, 194 (range, 94-460) and 184 (range, 105-342). No severe complication was associated with PP, but 5 patients developed pressure sores and 2 others had superficial sternal wound infections. Intensive care unit mortality of 37.5% reflected the number of organ failure(s); there were no deaths with 2 failures, and 60% with > or = 3 organ failures died (p = 0.03). Mortality rates were comparable regardless of whether patients were PaO(2)/F(I)O(2) responders or their PaCO(2) decreased by > or = 1 mmHg. CONCLUSION: PP to treat ARDS after cardiac surgery is feasible, safe, and can efficiently improve oxygenation. Measures to prevent pressure sores are mandatory.

Aortic valve replacement for low-flow/low-gradient aortic stenosis operative risk stratification and long-term outcome: a European multicenter study.

OBJECTIVES: We evaluated a large multicenter series of patients operated on for low-flow/low-gradient aortic stenosis (LF/LGAS) to stratify the operative risk, assess whether perioperative mortality has decreased over recent years, and analyze the post-operative outcome. BACKGROUND: Although LF/LGAS is classically associated with a high operative risk, few data are available concerning the results of surgery in this setting. METHODS: A total of 217 consecutive patients (168 men, 77%) with severe aortic stenosis (area <1 cm(2)), low ejection fraction (EF) (

Outcome after valve replacement for severe aortic stenosis associated with reduced left ventricular ejection fraction.

BACKGROUND AND AIM OF THE STUDY: Because valve replacement for aortic stenosis (AS) remains a difficult surgical challenge in the presence of left ventricular dysfunction, the immediate and long-term outcomes, and evolution of left ventricular ejection fraction (LVEF) in this setting, were analyzed. METHODS: Forty-three consecutive patients with severe AS (valve area < or =1 cm2) and reduced LVEF (< or =40%) who underwent valve replacement surgery at the authors' institution between April 1998 and December 2003 and were studied retrospectively. RESULTS: Preoperative characteristics included: LVEF 33 +/- 6%, mean transaortic pressure gradient 46 +/- 13 mmHg, and aortic valve area 0.58 +/- 0.15 cm2. Concomitant coronary artery bypass grafting was performed in 15 patients (35%). Perioperative (30-day) mortality was 2.3%, with 39.5% morbidity. During a mean follow up of 33.4 +/- 17.6 months, eight patients died. The Kaplan-Meier estimate of five-year survival was 75.3%. Postoperatively, none of the survivors remained in NYHA functional classes III-IV. The postoperative LVEF assessed in 81.8% of survivors had improved. Multivariate analysis associated improved LVEF with a higher preoperative mean transaortic pressure gradient (p = 0.0009) and a higher preoperative LVEF (p = 0.02). CONCLUSION: Patients with severe AS and reduced LVEF can undergo valve replacement with low perioperative mortality and moderate postoperative morbidity. Good long-term survival with good NYHA functional status and improved LVEF can be obtained.

Computation of dynamical correlation functions of heisenberg chains in a magnetic field.

We compute the momentum- and frequency-dependent longitudinal spin structure factor for the spin-1/2 XXZ Heisenberg spin chain in a magnetic field, using exact determinant representations for form factors on the lattice. Multiparticle (i.e., multispinon) contributions are computed numerically throughout the Brillouin zone, yielding saturation of the sum rule to high precision.

Critically ill old and the oldest-old patients in intensive care: short- and long-term outcomes.

OBJECTIVE: The purpose of this study was to examine characteristics and outcome of the old, very old and oldest-old ICU patients DESIGN. This is a cohort study. SETTING: The study was set in a ten-bed medical ICU in a university hospital. PARTICIPANTS. There were 410 patients classified in three subgroups: old, 75-79 years ( n=184; 44.4%), very old, 80-84 ( n=137, 33.4%) and the oldest-old, >or=85 ( n=91; 22.2%). MEASUREMENTS: Underlying medical conditions, organ dysfunction, severity of illness, length of stay, use of mechanical ventilation, therapeutic activity and nosocomial infections were recorded. Multivariate analysis was conducted to identify risk factors for ICU and long-term mortality. RESULTS: Characteristics at ICU admission did not differ among the three groups. ICU length of stay, therapeutic activity, mechanical ventilation and nosocomial infection(s) decreased with age. ICU survival rates for those below 75, 75-79, 80-84 and over 85 years were 80, 68, 75 and 69%, respectively; survival rates at 3 months were 54, 56 and 51%, respectively. APACHE II score [odds ratio (OR): 1.11] was identified as the only factor associated with ICU mortality, and age (OR: 2.17, for patients >or=85 years old and 1.82, for patients 80-84 years old) and limitation of activity before admission (OR: 1.74) as factors associated with long-term mortality. CONCLUSION: In a population of patients >or=75 years old, very old age is not directly associated with ICU mortality. After ICU discharge, deaths occurred predominantly during the first 3 months: age and prior limitation of activity were associated with the risk of dying.

Efficacy of esmolol as a myocardial protective agent during continuous retrograde blood cardioplegia.

OBJECTIVE: Esmolol, an ultra-short-acting beta-blocker, is known to attenuate myocardial ischemia-reperfusion injury. The aim of this study was to compare the effects of esmolol and potassium on myocardial metabolism during continuous normothermic retrograde blood cardioplegia. METHODS: Forty-one patients operated on for isolated aortic valve stenosis were randomly assigned to continuous coronary infusion with either potassium or esmolol during cardiopulmonary bypass. Myocardial metabolism was assessed by measuring the transmyocardial gradient of oxygen content indexed to left ventricular mass of glucose, lactate, and nitric oxide. To do so, blood samples were simultaneously withdrawn upstream (in the cardioplegia line) and downstream of the myocardium (in the left coronary ostium) 10 and 30 minutes after aortic crossclamping. RESULTS: Although the cardioplegia flow rate and pressure were similar, esmolol markedly reduced the transmyocardial gradient of oxygen content indexed to left ventricular mass compared with potassium: 13 +/- 6 vs 20 +/- 6 mL of oxygen per liter of blood per 100 g of myocardium, respectively, at 10 minutes and 16 +/- 8 vs 24 +/- 8 mL of oxygen per liter of blood per 100 g of myocardium, respectively, at 30 minutes (P =.009). Coronary glucose and lactate transmyocardial gradients were similar in both groups, indicating adequate myocardial perfusion in all patients at all times. In addition, during retrograde cardioplegia, esmolol showed a lower nitric oxide release compared with that caused by potassium (39 +/- 49 micro mol x L(-1) for potassium vs 14 +/- 8 micro mol x L(-1) for esmolol at 10 minutes and 39 +/- 47 micro mol x L(-1) for potassium vs 6 +/- 8 micro mol x L(-1) for esmolol at 30 minutes, P =.05). However, hemodynamic parameters and plasma troponin I levels remained unchanged postoperatively between the 2 types of cardioplegia. CONCLUSION: Esmolol provides potent myocardial protection in hypertrophied hearts, at least in part, by reducing myocardial oxygen metabolism.

Frequency, risk factors, and outcome of hyperlactatemia after cardiac surgery.

STUDY OBJECTIVE: To determine the respective frequencies, risk factors, and outcomes of no hyperlactatemia (NHL), immediate hyperlactatemia (IHL), or late hyperlactatemia (LHL) > 3 mmol/L after cardiac surgery. DESIGN: Prospective and observational study. SETTING: Cardiac surgery ICU in a 130-bed private community nonteaching hospital. PATIENTS: Consecutive patients (n = 325) undergoing cardiopulmonary bypass (CPB) for cardiac surgery. INTERVENTION: None. MEASUREMENTS: Arterial blood gas levels and lactate concentrations were measured at ICU admission, 4 h after surgery, between 6 h and 16 h after surgery, and on day 1. MAIN RESULTS: Sixty-seven patients (20.6%) had an IHL on ICU admission, and 56 patients (17.2%) acquired LHL during their ICU stay. ICU mortality was 1.5% for NHL, 3.6% for LHL, and 14.9% for IHL groups (p < 0.0001). The three groups differed significantly for elective surgery, type of operation, CPB duration, intraoperative mean arterial pressure, and intraoperative and postoperative use of vasopressor. Independent risk factors for IHL were nonelective surgery, CPB duration, and intraoperative use of vasopressor. Logistic regression identified hyperglycemia and epinephrine therapy for LHL as postoperative risk factors. Receiver operating characteristic curves showed that IHL more accurately predicted ICU mortality than LHL. CONCLUSIONS: Hyperlactatemia is common after cardiac surgery. A lactate threshold of 3 mmol/L at ICU admission is able to identify a population at risk of morbidity and mortality after cardiac surgery.