Clinically Important Misclassification of Aortic Valve Stenosis Severity Using Non-Invasive Techniques: Simultaneous Echocardiography and Cardiac Catheterization During Transcatheter Aortic Valve Implantation in Awake Patients.

BACKGROUND: Suitability for transcatheter aortic valve (AV) implantation (TAVI) is determined by using transthoracic echocardiography (TTE), although left-sided cardiac catheterization (LCC) provides directly measured pressure data. TAVI in awake patients permits simultaneous comparison of TTE and LCC under physiologically relevant left ventricular loading conditions. We hypothesized that clinically important discrepancies between TTE and LCC would be identified. METHODS AND RESULTS: TAVI was performed in 108 awake patients undergoing intra-procedural TTE and LCC between January 1, 2016 and December 31, 2016, based upon pre-procedure TTE data. Intra-procedural assessments simultaneously were performed before and after prosthesis implantation. Based upon mean trans-AV systolic ejection pressure gradient (MSEPG), AS was graded as: mild (<20 mm Hg; grade 1), moderate (20 - <40 mm Hg; grade 2), or severe (≥40 mm Hg; grade 3). In 79 of the 108 (73.1%) patients, intra-procedural TTE and LCC assessments were concordant. In 2 of the 108 (1.9%) patients, TTE overestimated AS severity by ≥1 grade. In 27 of the 108 (25.0%) patients, TTE underestimated AS severity by ≥1 grade. In total, AS severity reclassification occurred in 29 (26.9%) patients. Overall, TTE underestimated MSEPG by 8.9 ± 1.2 mm Hg (TTE MSEPG versus LCC MSEPG; P < .001). CONCLUSION: Current TTE criteria appear to frequently and importantly underestimate AS severity. Because decision-making regarding TAVI often exclusively is based upon TTE data, these findings suggest either a continued role for LCC in the diagnostic assessment of AS in patients who do not meet standard TTE criteria or lowering TTE cutoffs for TAVI.

Gastrointestinal Complications After Cardiac Surgery: A Nationwide Population-Based Analysis of Morbidity and Mortality Predictors.

OBJECTIVE: The authors aimed to evaluate the incidence, risk factors, and outcomes of gastrointestinal (GI) complications in cardiac and aortic surgery using recent versions of the National (Nationwide) Inpatient Sample (NIS) to provide clinicians with a better understanding of these uncommon but potentially serious complications. DESIGN: Population-based study. SETTING: NIS database 2010-2012. PARTICIPANTS: Patients undergoing cardiac and aortic aneurysm repair surgeries. INTERVENTIONS: Not applicable. MEASUREMENTS AND MAIN RESULTS: The most common GI complication was postoperative ileus, which also had the lowest mortality, followed by GI hemorrhage. Mesenteric ischemia demonstrated the highest mortality, followed by intestinal perforation. Mortality was highest in those with infective endocarditis (16.02%), followed by myocardial infarction (12.48%). GI complications were highest in patients undergoing repair of abdominal aortic aneurysm, followed by off-pump coronary artery bypass grafting. CONCLUSION: In conclusion, this study demonstrated that GI complications after cardiac surgery occurred at a rate of 4.17%, which is similar to that reported in the NIS database from 1998 to 2002 in coronary artery bypass grafting patients, but higher than that previously described in single-center studies. GI complications after cardiac surgery increased inpatient mortality 3-fold and more than doubled length of stay. Improved recognition and understanding of the predisposing risk factors and complications elucidated in this study could serve to increase the necessity for timely diagnosis and treatment of patients at high risk for GI complications after cardiac surgery.

Propensity and impact of autologous platelet rich plasma use in acute type A dissection.

BACKGROUND: Coagulopathy in patients undergoing open repair of acute type A aortic dissection using cardiopulmonary bypass and hypothermic circulatory arrest is a common complication. Autologous platelet rich plasma is an intraoperative blood conservation technique, which has been shown in previous studies to promote hemostasis, leading to a reduction of blood product transfusions during elective aortic surgery. The purpose of this study is to evaluate the effectiveness of autologous platelet rich plasma as a blood conservation technique during open surgical repair of acute type A aortic dissection. METHODS: We reviewed all acute type A aortic dissection cases using hypothermic circulatory arrest, excluding patients presenting in extremis. Perioperative transfusion requirements and clinical outcomes were analyzed. The end points analyzed included early mortality, postoperative stroke, renal dysfunction, prolonged ventilation, coagulopathy, and length of postoperative intensive care unit stay. Parsimonious and saturated propensity scores were calculated for platelet rich plasma use, and all outcomes were propensity adjusted. RESULTS: Between 2003 and 2014, 85 of 391 acute type A aortic dissection repairs used autologous platelet rich plasma. Mean age of patients was 58 ± 15 years, and 70% were male. Obstructive sleep apnea (22% vs 13%, P = .04) and baseline ejection fraction (57% ± 6.7% vs 55% ± 10%; P = .014) were higher in the autologous platelet rich plasma group. Intraoperative propensity-adjusted blood products, 2 units fewer packed red blood cells (P = .001), 4 units fewer fresh-frozen plasma (P = .001), 6 units fewer platelets (P = .001), 1.3 units fewer cell-savers (P = .002), and 5 units fewer cryoprecipitate (P = .001) were significantly reduced by autologous platelet rich plasma use. Significant unadjusted reduction in postoperative reoperation for bleeding (8% vs 17%, P = .046) after autologous platelet rich plasma was reported, although propensity adjustment eliminated significance (P = .079). No difference in stroke, cardiac, or renal complications was observed. Postoperative transfusion needed during the first 3 days was significantly reduced in the autologous platelet rich plasma group: 2 units fewer packed red blood cells (P = .13), 2 units fewer fresh-frozen plasma (P = .018), and 5 units fewer platelets (P = .001), when compared with those without autologous platelet rich plasma. Ventilation time was reduced by 3 days (P = .002), and intensive care length of stay was reduced by 3 days (P = .063) after intraoperative autologous platelet rich plasma use. CONCLUSIONS: The use of autologous platelet rich plasma in patients undergoing open repair of acute type A aortic dissection was associated with a reduction in intraoperative and postoperative blood transfusions, as well as decreased early postoperative morbidity.

Analysis of motor and somatosensory evoked potentials during thoracic and thoracoabdominal aortic aneurysm repair.

OBJECTIVES: Use of motor evoked potentials (MEP) and somatosensory evoked potentials (SSEP) monitoring during thoracic and thoracoabdominal aortic surgery is controversial. This study evaluated the intraoperative use of SSEP and MEP during thoracoabdominal repair and assessed their role in decreasing the risk of spinal cord ischemia and paralysis. METHODS: We conducted paired SSEP and MEP monitoring to assess agreement between the methods and their ability to predict neurologic outcome in 233 patients. Changes in SSEP and MEP monitoring were classified as no change, reversible change, or irreversible change during the intraoperative period and by the conclusion of surgery. Agreement between the methods was computed using the Cohen kappa statistic. Sensitivity, specificity, and positive and negative predictive values were computed for each method on the immediate and delayed neurologic deficit. RESULTS: Immediate neurologic deficit, determined immediately upon awakening from anesthesia and confirmed by a neurologist, occurred in eight of 233 (3.4%) patients. For any change (reversible plus irreversible), agreement between MEP and SSEP was relatively low (kappa = 0.53), despite being highly statistically significant (P < .001). MEP tended to overestimate SSEP for immediate neurologic deficit, demonstrating a 53% false-positive rate, compared with a 33% false-positive rate for SSEP (specificity ratio, 1.42; P < .0001). With irreversible change, agreement between the methods was 90% (kappa = 0.896, P < .0001). Only irreversible change was significantly associated with neurologic outcome (odds ratio, 21.9; P < .00001 for SSEP; 60.8, P < .0001 for MEP), but sensitivity and positive predictive values were low (37% and 33% for SSEP; 22% and 45% for MEP, respectively). Reversible changes in neurophysiologic monitoring were not significantly associated with immediate neurologic deficit. Negative predictive values for all negative evoked potential findings were >98% for immediate deficit. No evoked potential variables were associated with delayed deficit. CONCLUSIONS: SSEP and MEP monitoring were highly correlated only when intraoperative changes were irreversible. Reversible changes were not significantly associated with immediate neurologic deficit. Irreversible changes were significantly associated with immediate neurologic deficit, and the findings were identical for SSEP and MEP in this variable, indicating that the more complex MEP measures do not add further information to that obtained from SSEP. Normal SSEP and MEP findings had a strong negative predictive value, indicating that patients without signal loss are unlikely to awake with neurologic deficit.

Systolic anterior motion of the mitral valve after aortic valve replacement.

We present a case of severe systolic anterior motion developing intraoperatively after aortic valve replacement for aortic valve stenosis.

Intraoperative assessment of pulmonary artery pressure using transesophageal echocardiography in patients undergoing cardiac surgery.

We performed a retrospective chart review to investigate a potential relation between pulmonary artery (PA) diameter as measured by intraoperative transesophageal echocardiography and PA pressures measured by PA catheter with the aim of determining whether main PA diameter can aid clinicians in the diagnosis of PA hypertension. A total of 82 adult patients undergoing cardiac surgery were included in our study. Main PA diameter showed a moderate correlation with systolic and diastolic pressures, r = 0.576 (95% confidence interval [CI], 0.407-0.703), P < 0.001, and r = 0.504 (95% CI, 0.319-0.648), P < 0.001, respectively. The authors believe that although a moderate correlation exists between main PA diameter and PA pressure, confounding hemodynamic variables prevent main PA diameter from being an accurate and reliable means of diagnosing PA hypertension.

Unsuccessful Redo MitraClip Procedure Leads to Acute Right Ventricular Failure in a Patient With Homozygous Familial Hypercholesterolemia and a Preexisting Atrial Septal Defect.

The MitraClip procedure is an emerging endovascular technique for treating mitral regurgitation and an attractive alternative for patients who are at high risk for open heart mitral valve repair or replacement. We present the case of a failed redo MitraClip procedure that led to acute right ventricular failure in a patient with homozygous familial hypercholesterolemia and a preexisting secundum atrial septal defect. We highlight the sequelae of the failed redo MitraClip procedure and the anesthetic challenges associated with the emergent redo sternotomy and cardiopulmonary bypass procedure required to replace the mitral valve and repair the tricuspid valve and atrial septal defect.

Cerebral monitoring with transcranial Doppler ultrasonography improves neurologic outcome during repairs of acute type A aortic dissection.

OBJECTIVE: Neurologic complications after repair of acute type A aortic dissection remain significant. The use of power M-mode transcranial Doppler monitoring to verify cerebral blood flow during these repairs might decrease cerebral ischemia by correcting malperfusion. The purpose of this study was to analyze the use of power M-mode transcranial Doppler monitoring during repairs of acute type A dissection with regard to neurologic outcome. METHODS: We performed a prospective study of patients undergoing repairs of acute type A aortic dissection. Repairs included profound hypothermic circulatory arrest and retrograde cerebral perfusion. Patients in whom transcranial Doppler monitoring was used to monitor cerebral blood flow and modify operative technique during repair (study group) were compared with those without monitoring and modification (control group). RESULTS: Between September 2001 and October 2003, we repaired 56 cases of acute type A dissection. Power M-mode transcranial Doppler monitoring was used in 50% (28/56) of cases. Power M-mode transcranial Doppler monitoring altered operative cannulation and guided retrograde cerebral perfusion flow in 28.5% (8/28) and 78.6% (22/28) of cases, respectively. Two patients presented with preoperative stroke, one in each group. One operative death occurred in each group. In-hospital mortality and the occurrence of new stroke were not significantly different between the 2 groups. Temporary neurologic dysfunction occurred less often in the study group (14.8% [4/27] vs 51.8% [14/27], P = .008). CONCLUSIONS: Identification of cerebral malperfusion requires cerebral monitoring. By ensuring cerebral blood flow by using power M-mode transcranial Doppler monitoring and correcting cerebral malperfusion by modifying operative technique, neurologic outcome was improved during repairs of acute type A aortic dissection.

Autologous platelet-rich plasma reduces transfusions during ascending aortic arch repair: a prospective, randomized, controlled trial.

BACKGROUND: Blood conservation using autologous platelet-rich plasma (aPRP), a technique of whole blood harvest that separates red blood cells from plasma and platelets before cardiopulmonary bypass with retransfusion of the preserved platelets after completion of cardiopulmonary bypass, has not been studied extensively. We sought to prospectively determine whether aPRP reduces blood transfusions during ascending and transverse aortic arch repair. METHODS: We randomly assigned 80 patients undergoing elective ascending and transverse aortic arch repair using deep hypothermic circulatory arrest to receive either aPRP (n = 38) or no aPRP (n = 42). Volume of aPRP retransfused was 726 ± 124 mL. The primary end point was transfusion amount. Secondary end points were death, stroke, renal failure, pulmonary failure, and transfusion costs. Perioperative transfusion rate was defined as blood transfusions given during surgery and up to 72 hours afterward. The surgeon and intensivist were blinded to the treatment arm. Because an anesthesiologist initiated the protocol, the surgeon was not aware of aPRP collection, as this occurred only after the sterile drape was in place. In addition, because cell salvage was performed on all cases, differentiation in perfusionist activities (during spinning of aPRP) was not evident. Platelet, fresh frozen plasma, and cryoprecipitate intraoperative transfusions were performed only after heparin was reversed and the patient was judged as coagulopathic on the basis of associated criteria: cryoprecipitate transfusion for fibrinogen level less than 150 µg/dL, platelet transfusion for platelet count less than 80,000, and fresh frozen plasma when thromboelastogram test was suggestive or a partial thromboplastin time was greater than 55 seconds, and prothrombin time was greater than 1.6 seconds. RESULTS: Early mortality, stroke, and respiratory complications were similar between groups. Only acute renal failure was reduced in the aPRP group, 7% versus 0% (p < 0.014). Mean transfusion rate of packed red blood cells was reduced by 34%, fresh frozen plasma by 52.8%, cryoprecipitate by 70%, and platelets by 56.7% in the aPRP group (p < 0.02). Hospital length of stay (9.4 ± 5.3 days versus 12.7 ± 6.3 days; p < 0.014) and transfusion costs ($1,396 ± $1,755 versus $2,762 ± $2,267; p < 0.004) were reduced in the aPRP group. CONCLUSIONS: The use of aPRP reduced allogeneic transfusions during ascending and transverse aortic arch repair with deep hypothermic circulatory arrest. This translated to less acute renal failure, decreased length of stay, and lower transfusion costs. Further studies examining the coagulation factors of aPRP are required.

Preoperative and operative predictors of delayed neurologic deficit following repair of thoracoabdominal aortic aneurysm.

PURPOSE: Delayed neurologic deficit has been recognized in recent years as a source of morbidity following thoracic and thoracoabdominal aortic repair. We wanted to find risk factors specifically significant for delayed neurologic deficit. In this initial study we looked at preoperative and operative risk factors. METHODS: We performed 854 thoracoabdominal aortic repairs between February 1991 and May 2001. For this study we excluded 26 patients who died before postoperative neurologic status could be evaluated and 38 who had immediate neurologic deficit on initial postoperative evaluation, leaving 790 consecutive patients. We evaluated a wide range of demographic, preoperative physiological and intraoperative data, using univariate and multivariable statistical analyses. RESULTS: Twenty-one of 790 (2.7%) patients had delayed neurologic deficit. Significant univariate predictors included preoperative renal dysfunction (odds ratio 5.9; P <.006), acute dissection (odds ratio 3.9; P <.05), extent II thoracoabdominal aorta (odds ratio 3.0; P <.03), and use of adjuncts (cerebrospinal fluid drainage and distal aortic perfusion; odds ratio 7.7; P <.03). The use of the adjuncts dropped from the multivariable model but all other factors remained. No other significant risk factors were identified. Twelve of 21 (57%) patients recovered neurologic function with optimization of blood pressure and cerebrospinal fluid drainage. CONCLUSION: Preoperative renal dysfunction, acute dissection, and extent II thoracoabdominal aorta are significant predictors of delayed neurologic deficit. Previous studies have demonstrated that the use of adjuncts protects against immediate neurologic deficit. The findings of this study are consistent with the hypothesis that adjuncts reduce ischemic insult enough to prevent immediate neurologic deficit but that a period of increased spinal cord vulnerability persists several days postoperatively.

Contemporary strategies to preserve renal function during cardiac and vascular surgery.

Mortality rates associated with perioperative acute renal failure (ARF) range from 60% to 90%. The major causes of ARF are prerenal factors that decrease renal blood flow; intrarenal factors that have a direct effect on tubules, interstitium, or glomeruli; and postrenal factors that obstruct urine outflow. Current strategies to provide perioperative renal protection include maintaining adequate renal O2 delivery, suppressing renovascular vasoconstriction, renovascular vasodilatation, maintaining tubular flow, decreasing renal cellular O2 consumption, and attenuating reperfusion injury. A study of patients undergoing elective repair of a thoracoabdominal aortic aneurysm (TAAA) found that the use of the selective dopamine-1 receptor agonist fenoldopam was associated with reductions in mortality, dialysis requirements, and lengths of stay in the hospital and intensive care unit. The study authors suggest that the improved patient outcomes and hospital-utilization data resulting from the use of fenoldopam were directly related to the protection of renal function during surgery and a reduction of postoperative renal complications.

Determination of cerebral blood flow dynamics during retrograde cerebral perfusion using power M-mode transcranial Doppler.

BACKGROUND: Retrograde cerebral perfusion (RCP) during profound hypothermic circulatory arrest has been used as an adjunct for cerebral protection for repairs of the ascending and transverse aortic arch. Transcranial Doppler ultrasound has been used to monitor cerebral blood flow during RCP with varying success. The purpose of this study was to characterize cerebral blood flow dynamics during RCP using a new mode of monitoring known as transcranial power motion-mode (M-mode) Doppler ultrasound. METHODS: Data on pump-flow characteristics and patient outcomes were collected prospectively for patients undergoing ascending and transverse aortic arch repair. Retrograde cerebral perfusion during profound hypothermic circulatory arrest was used for all operations. Intraoperative cerebral blood flow dynamics were monitored and recorded using transcranial power M-mode Doppler ultrasound. RESULTS: Between August 2001 and March 2002, we used transcranial power M-mode Doppler ultrasound monitoring for 40 ascending and transverse aortic arch repairs during RCP. Mean RCP time was 32.2 +/- 13.8 minutes. Mean RCP pump flow and RCP peak pressure for identification of cerebral blood flow were 0.66 +/- 0.11 L/min and 31.8 +/- 9.7 mm Hg, respectively. Retrograde cerebral blood flow during RCP was detected in 97.5% of cases (39 of 40 patients) with a mean transcranial power M-mode Doppler ultrasound flow velocity of 15.5 +/- 12.3 cm/s. In the study group, 30-day mortality was 10.0% (4 of 40 patients). The incidence of stroke was 7.6% (3 of 40 patients); the incidence of temporary neurologic deficit was 35.0% (14 of 40 patients). CONCLUSIONS: Transcranial power M-mode Doppler ultrasound consistently demonstrated retrograde middle cerebral artery blood flow during RCP. Transcranial power M-mode Doppler ultrasound can provide optimal RCP with individualized settings of pump flow.

Analysis of autologous platelet-rich plasma during ascending and transverse aortic arch surgery.

BACKGROUND: Coagulopathy is a common complication after ascending and transverse arch aortic surgery with profound hypothermic circuit arrest (PHCA). Blood conservation strategies to reduce transfusion have been ongoing and involve multiple treatment modalities in modern cardiac surgery. The purpose of this study is to evaluate the effectiveness of autologous platelet-rich plasma (aPRP) as a blood conservation technique to reduce blood transfusion in ascending and arch aortic surgery. METHODS: Between 2003 and 2009, we retrospectively reviewed 685 cases of ascending aorta and transverse arch repair using PHCA. A total of 287 patients in which aPRP was used (aPRP group) were compared with 398 patients who did have aPRP (non-aPRP group). Perioperative transfusion requirements and clinical outcomes that included early mortality, postoperative stroke, renal dysfunction, prolonged ventilation, coagulopathy, and length of postoperative intensive care unit stay were analyzed. The data were analyzed by mean and frequency for continuous variables and qualitative variables. To account for potential selection bias, 2 types of propensity analysis were performed. RESULTS: In both unadjusted and adjusted analysis, perioperative transfusions were fewer in the aPRP group compared with the non-aPRP group: (3.9 units fewer packed red blood cells, 4.5 units fewer fresh frozen plasma, 7.9 units fewer platelets, and 6.8 units fewer cryoprecipitate). In all analyses, postoperative morbidity (stroke, duration of mechanical ventilation, and intensive care unit stay) were significantly improved. Hospital mortality rate was not significantly decreased. CONCLUSIONS: The utilization of aPRP was associated with a reduction in allogeneic blood transfusions as well as a decrease in early postoperative morbidity during repairs of the ascending and transverse arch aorta using PHCA.