Search PubMed⌕ Search

Biomedical subjects

Thoralf M Sundt

Publications and source records attributed to Thoralf M Sundt.

At least 19 recordsLinked to original sources
PubMed2007

Simple risk models to predict surgical mortality in acute type A aortic dissection: the International Registry of Acute Aortic Dissection score.

BACKGROUND: Surgical mortality for acute type A aortic dissection is frequently related to preoperative clinical conditions. We report a predictive score to identify risk of death that may be helpful to assist surgeons who are considering whether to proceed with surgical correction in the case of patients in extreme clinical risk. METHODS: Surgical outcome of 682 patients enrolled in the International Registry of Acute Aortic Dissection from 1996 to 2003 was analyzed. Two different models were used. The initial model included only preoperative variables such as demographics, history, symptoms, signs, and diagnostic methods (model 1). The second model also tested intraoperative hemodynamic and surgical variables (model 2). A bedside risk prediction tool to predict operative mortality in individual patients was developed. RESULTS: The overall in-hospital surgical mortality was 23.9%. Independent preoperative predictors of mortality in model 1 were age greater than 70 years, prior cardiac surgery, hypotension (systolic blood pressure less than 100 mm Hg) or shock at presentation, migrating pain, cardiac tamponade, any pulse deficit, and electrocardiogram with findings of myocardial ischemia or infarction. In model 2, other predictors of surgical death were intraoperative hypotension, a right ventricle dysfunction at surgery, and a necessity to perform coronary revascularization. An independent predictor for favorable surgical outcome was right hemiarch replacement. CONCLUSIONS: Surgery in unstable patients with acute type A aortic dissection can be highly unsuccessful. The International Registry of Acute Aortic Dissection risk models predict in-hospital mortality using a multivariable risk prediction tool, useful for surgeons and patients as they consider their surgical risk and the pros and cons of embarking on high-risk surgery.

Acute Disease↗
PubMed2007

Does preoperative atrial fibrillation influence early and late outcomes of coronary artery bypass grafting?

OBJECTIVE: The study objective was to describe the independent effect of preoperative atrial fibrillation on the outcome of coronary artery bypass grafting, including the causes of death (cardiac vs noncardiac). METHODS: We analyzed the outcome of patients with preoperative atrial fibrillation who underwent on-pump coronary artery bypass grafting between 1993 and 2002 and compared them with matched controls in sinus rhythm; matching variables were age, gender, ejection fraction, and numbers of diseased coronary arteries and distal anastomoses. Direct patient follow-up focused on late complications and reinterventions, and we investigated causes for all deaths. RESULTS: Operative mortality (1.6% vs 1.9%, P = .79) was similar in patients with preoperative atrial fibrillation (n = 257) compared with patients in sinus rhythm (n = 269). The patients with atrial fibrillation had longer hospital stays (9 +/- 6 days vs 8 +/- 6 days, P = .0008) and a trend to more frequent early readmissions (13% vs 9%, P = .08). During follow-up (median 6.7 years, maximum 12 years), late hospital admission was more frequent in patients with atrial fibrillation (59% vs 31%, P < .0001). Risk of late mortality (all causes) in patients with atrial fibrillation was increased by 40% compared with patients in sinus rhythm (P = 0.02), and the late cardiac death rate in the atrial fibrillation group was 2.8 times that of the sinus rhythm group (P = .0004). Major adverse cardiac events occurred in 70% of patients with preoperative atrial fibrillation compared with 52% of patients in preoperative sinus rhythm (P < .0001). Subsequent rhythm-related intervention, including pacemaker implantations, was more common in the atrial fibrillation group (relative risk = 2.1, P = .0027). CONCLUSIONS: Uncorrected preoperative atrial fibrillation in patients undergoing coronary artery bypass grafting is associated with increased late cardiac morbidity and mortality and poor long-term survival. These data support consideration of atrial fibrillation surgery at the time of coronary artery bypass grafting.

Aged↗
PubMed2006

Systolic anterior motion after mitral valve repair: is surgical intervention necessary?

OBJECTIVE: The natural history and management of patients with systolic anterior motion after mitral valve repair are uncertain. METHODS: We performed a retrospective chart review and survey follow-up of all patients in whom systolic anterior motion developed intraoperatively after mitral valve repair. RESULTS: From January 1993 to December 2002, mitral valve repair was performed in 2076 patients, and in 174 cases (8.4%) systolic anterior motion was identified on intraoperative echocardiography. These patients form the study group. Initially, patients were managed with a combination of beta-blockade, vasoconstriction with phenylephrine, and/or intravascular volume expansion. Four patients had revision of repair because of persistent systolic anterior motion, and 3 additional patients had revision of repair because of mitral regurgitation from other causes. The median follow-up of the remaining 167 patients was 5.4 years (range 0-13.2 years). There were 2 late reoperations, but none were caused by systolic anterior motion or left ventricular outflow tract obstruction. Ninety percent of patients were in New York Heart Association class I, 7% were in class II, and 3% were in class III or IV. Echocardiograms were available for review in 93 patients at a median interval of 5.4 years (range 0.2-12.2 years); 13 patients had systolic anterior motion, and 4 patients had systolic anterior motion with left ventricular outflow tract obstruction. CONCLUSIONS: In this experience, most cases of systolic anterior motion resolved with conservative measures including beta-blockade, vasoconstriction, and fluid administration. Persistent systolic anterior motion with left ventricular outflow tract obstruction was documented in 2.3% of patients who had early systolic anterior motion, but late reoperation was not required. Furthermore, the clinical outcomes of patients with systolic anterior motion are comparable to the current norms for mitral valve repair. Ninety percent of patients were in New York Heart Association class I, 7% were in class II, and 3% were in class III or IV.

Adult↗
PubMed2006

Recurrent mitral regurgitation after repair: should the mitral valve be re-repaired?

OBJECTIVE: We sought to evaluate the clinical and echocardiographic outcomes of reoperation for failed mitral valve repair. METHODS: One hundred forty-five patients with recurrent mitral regurgitation after primary mitral valve repair of degenerative leaflet prolapse underwent mitral valve reoperations between January 1, 1970, and January 1, 2005. The mean age was 66 years, and 102 (70%) were men. RESULTS: The mean duration from initial repair to reoperation was 4.1 years (standard deviation = +/- 5.1 years). Indications for reoperation were regurgitation alone (n = 109 [75%]), hemolysis (n = 27 [19%]), obstruction from systolic anterior motion (n = 3 [2%]), endocarditis (n = 3 [2%]) and stenosis-other (n = 3 [2%]). New pathology was found in 80 (55%) patients, and failure of the initial repair was found in 61 (42%) patients. The mitral valve was re-repaired in 64 (44%) patients and replaced in 81 (56%) patients. Early operative mortality was similar after re-repair and replacement (1.6% vs 4.9%, P = .38). Independent predictors of improved survival on multivariate analysis were mitral re-repair (hazard ratio = 0.44, P = .03), younger age (hazard ratio = 1.06, P = .001), and an operative indication of mitral regurgitation alone (hazard ratio = 0.31, P = .005). Seven patients had a third mitral operation (all replacements), 6 after re-repair and 1 after replacement. At last follow-up echocardiogram (n = 96), ejection fraction was greater (P < .001) and left ventricular end-systolic dimension was smaller (P = .009) in patients undergoing re-repair compared with values in those undergoing valve replacement. CONCLUSION: Recurrent mitral regurgitation after prior repair is frequently caused by new valve pathology. Mitral re-repair is performed in almost half of patients and is associated with superior survival, improved ejection fraction, and greater regression in ventricular dimension compared with valve replacement.

Aged↗
PubMed2006

Surgical correction of mitral regurgitation in the elderly: outcomes and recent improvements.

BACKGROUND: In the elderly, mitral regurgitation (MR) is frequent, but surgery risks are considered high. Benefits and indications of MR surgery are uncertain in the elderly. METHODS AND RESULTS: Baseline characteristics, outcome, and trends for surgical results improvement were analyzed in elderly patients (> or = 75 years of age; n=284) operated on for MR in 1980 to 1995 compared with younger patients (65 to 74 years of age, n=504; and <65 years of age, n=556). Preoperatively, class III to IV symptoms, atrial fibrillation, coronary disease, creatinine, and comorbidity index were more severe in elderly patients (all P<0.002). In the long term after surgery, observed survival stratified by age (> or = 75, 65 to 74, <65 years) was lower in elderly than in younger patients (at 5 years, 57+/-3%, 73+/-2%, and 85+/-2%, respectively; P<0.001), but ratios of observed to expected survival were similar (83%, 85%, and 88%, respectively). In multivariate analysis adjusted to expected survival, elderly patients showed no difference in life expectancy restoration compared with younger patients (adjusted hazard ratio, 0.89; 95% confidence interval, 0.73 to 1.30; P=0.54). Temporal trends showed that risk of operative mortality, although higher in elderly patients (P<0.001), declined markedly for all ages (27% to 5% in those > or = 75 years of age, P<0.01; 21% to 4% in those 65 to 74 years of age, P<0.01; and 7% to 2% in those <65 years of age, P=0.06), with a parallel decline in low cardiac output and length of hospital stay. Over time, valve repair feasibility increased in all age groups (30% to 84% overall and 31% to 93% in degenerative MR; P<0.0001). CONCLUSIONS: Elderly patients undergoing MR surgery display more severe preoperative characteristics and incur higher operative risks than younger patients. However, restoration of life expectancy after surgery is similar in elderly and younger patients, and outstanding recent surgical improvements particularly benefited elderly patients. Thus, elderly patients with MR can now carefully be considered for surgery before refractory heart failure is present.

Age Factors↗
PubMed2006

Role and results of surgery in acute type B aortic dissection: insights from the International Registry of Acute Aortic Dissection (IRAD).

BACKGROUND: The clinical profiles and outcomes of patients treated surgically for acute type B aortic dissection (ABAD) are often reported for those in small series or for those cared for at a single institution over a long time period, during which a continuous evolution in techniques has occurred. Accordingly, we sought to evaluate the clinical features and surgical results of patients enrolled in the International Registry of Acute Aortic Dissection by identifying primary factors that influenced surgical outcome and estimating average surgical mortality for ABAD in the current era. METHODS AND RESULTS: A comprehensive analysis of 290 clinical variables and their relation to surgical outcomes for 82 patients who required surgery for ABAD (from a population of 1256 patients; mean+/-SD age, 60.6+/-15.0 years; 82.9% male) and who were enrolled in the International Registry of Acute Aortic Dissection was performed. The overall in-hospital mortality was 29.3%. Factors associated with increased surgical mortality based on univariate analysis were preoperative coma or altered consciousness, partial thrombosis of the false lumen, evidence of periaortic hematoma on diagnostic imaging, descending aortic diameter >6 cm, right ventricle dysfunction at surgery, and shorter time from the onset of symptoms to surgery. Factors associated with favorable outcomes included radiating pain, normotension at surgery (systolic blood pressure 100 to 149 mm Hg), and reduced hypothermic circulatory arrest time. The 2 independent predictors of surgical mortality were age >70 years (odds ratio, 4.32; 95% confidence interval, 1.30 to 14.34) and preoperative shock/hypotension (odds ratio, 6.05; 95% confidence interval, 1.12 to 32.49). CONCLUSIONS: The present study provides insights into current-day clinical profiles and surgical outcomes of ABAD. Knowledge about different preoperative clinical conditions may help surgeons in making treatment decisions among these high-risk patients.

Acute Disease↗
PubMed2006

Valve replacement after T-grafting: "beating heart surgery".

Patent internal thoracic and radial artery T-graft will adequately perfuse the heart during reoperation. Five of 1,023 patients with prior T-grafting had aortic (3) or mitral valve redo operations in which the heart was allowed to beat (after an initial dose of cardioplegia) during the operation without clamping the patent T-graft. Rapid resumption of cardiac function after one dose of cardioplegia and no intraoperative or postoperative evidence of myocardial infarction indicated adequacy of perfusion without apparent myocardial injury. This approach avoids injury to the T-graft from dissection and clamping, saves time, and simplifies the operation.

Aged↗
PubMed2006

Thoracic aorta false aneurysm: what surgical strategy should be recommended?

BACKGROUND: Thoracic aorta false aneurysms (TAFA) are a surgical challenge. The best technical approach remains uncertain. METHODS: Between 1981 and 2004, 57 patients underwent operation for TAFA (mean age 57 +/- 18 years; 43 [75%] were male). Symptoms included dyspnea 25 (44%), chest pain 22 (39%), and fever 18 (32%). Twelve (21%) were asymptomatic. Thirty-seven (65%) had undergone previous operation with a mean interval between operations of 80 +/- 90 months. Fifteen (26%) had a mycotic etiology. The TAFA involved the aortic root in 10 (18%), ascending aorta in 28 (49%), arch in 6 (11%), and descending aorta in 13 (32%). Twenty-one (37%) required femorofemoral cannulation and 28 (49%), circulatory arrest. Surgical techniques included graft replacement in 27 (47%), composite root in 10 (18%), patch repair in 10 (18%), and direct suture in 10 (18%). RESULTS: Operative mortality was 7% (4 patients). Four of 32 (13%) had massive hemorrhage during redo sternotomy, and all of these had planned extramediastinal cannulation (all survived). Follow-up was 100% for 349 patient-years. Actuarial survival was 77% +/- 6%, 63% +/- 8%, and freedom from recurrent TAFA was 87% +/- 5% and 83% +/- 7%, at 5 and 10 years, respectively. Univariate analysis identified TAFA greater than 55 mm, urgent operation, and NewYork Heart Association functional class III or IV as predictors of hemorrhage during redo sternotomy. Obesity and ejection fraction of 35% or less were predictors of operative death. CONCLUSIONS: Thoracic aorta false aneurysm symptoms may be minimal, and consequently a high degree of suspicion plus serial imaging is warranted. Extramediastinal cannulation, deep hypothermia, and circulatory arrest are required for large mediastinal TAFA. Despite serious risks, TAFA correction is possible with good long-term results.

Adult↗
PubMed2006

Left ventricular dysfunction in atrial fibrillation: restoration of sinus rhythm by the Cox-maze procedure significantly improves systolic function and functional status.

BACKGROUND: Atrial flutter or fibrillation with rapid, uncontrolled ventricular response may lead to left ventricular dysfunction, and conversion to sinus rhythm with control of heart rate can improve left ventricular ejection fraction. Little is known about the effects of the Cox-maze procedure on this form of tachycardia-induced cardiomyopathy. METHODS: Four hundred forty-three patients underwent the Cox-maze procedure from 1993 to 2002. Ninety-nine had atrial flutter or fibrillation without associated valvular or congenital heart disease, and 37 (37%) had decreased left ventricular function (ejection fraction < 0.35 in 11 [severe], ejection fraction 0.36 to 0.45 in 8 [moderate], and ejection fraction 0.46 to 0.55 in 18 [mild]). Ages of these 37 patients (34 male) ranged from 35 to 74 years (median, 55 years). RESULTS: Atrial flutter or fibrillation was present for 3 months to 19 years (median, 48 months) preoperatively, and 24 patients (65%) exhibited symptoms of heart failure. Preoperative ejection fraction ranged from 0.25 to 0.55 (median, 0.45). At last follow-up (median, 63 months), the Cox-maze procedure eliminated atrial flutter or fibrillation in all but 1 patient, and the greatest improvement was observed in patients with severe preoperative impairment (0.31 to 0.53; p = 0.01, preoperative versus follow-up), and patients with preoperative chronic atrial flutter or fibrillation (0.43 to 0.55; p < 0.05 preoperative versus follow-up). This improvement was observed immediately postoperatively and was sustained at last follow-up. Further, improvement in left ventricular function correlated with enhancement of functional status. CONCLUSIONS: In some patients, atrial flutter or fibrillation may be the cause rather than the consequence of left ventricular dysfunction. Importantly, systolic function and functional status can be significantly improved with the restoration of sinus rhythm by the Cox-maze procedure.

Adult↗
PubMed2006

Survival advantage and improved durability of mitral repair for leaflet prolapse subsets in the current era.

BACKGROUND: Factors predicting long-term survival and reoperative risk after mitral valve repair for subsets with prolapse involving the anterior leaflet in the current era are unclear. METHODS: Between January 1, 1980 and December 31, 1999, surgical correction of mitral regurgitation was performed in 2,219 patients. We analyzed a subset of 1,411 patients with isolated mitral regurgitation due to leaflet prolapse undergoing mitral repair or replacement (+/- coronary bypass). RESULTS: Mean age was 64 years, and 1,003 (71%) were men. Mitral repair was performed in 1,173 (83%) patients. Factors independently predicting overall long-term survival included valve repair, younger age, better functional class, and the absence of significant coronary artery disease. After adjusting for these, smaller preoperative left ventricular end-systolic dimension and greater preoperative ejection fraction were associated with superior survival. Mitral reoperation occurred in 97 patients (75 repairs, 22 replacements), at a mean of 4.8 years after initial procedure. Cumulative risk of reoperation was similar for patients having valve repair or replacement. Factors predictive of need for reoperation after initial repair were younger age, anterior leaflet prolapse, chordal shortening, no leaflet resection, no prosthetic annuloplasty, greater than mild residual mitral regurgitation, and coronary artery disease. After valve replacement, the sole determinant of reoperation was use of a biological prosthesis. The durability of repair for prolapse of the anterior leaflet improved significantly during the second decade of the study. CONCLUSIONS: Mitral repair affords superior long-term survival, with permanence comparable with mechanical valve replacement. In all categories of mitral leaflet prolapse, durability of valve repair has improved over the past decade.

Age Factors↗
PubMed2006

Prognostic implications of preoperative atrial fibrillation in patients undergoing aortic valve replacement: is there an argument for concomitant arrhythmia surgery?

BACKGROUND: The prognostic significance of preoperative atrial fibrillation (AF) at the time of aortic valve replacement is unknown, as is the potential role for concomitant arrhythmia surgery. METHODS: We performed a cohort comparison of patients with preoperative AF (n = 129) and preoperative sinus rhythm (SR, n = 252) undergoing aortic valve surgery between 1993 and 2002; patients were matched for age, gender, and left ventricular ejection fraction. Follow-up (mean interval, 4.5 years) was 98% complete. Primary endpoints were late cardiac and all-cause mortality, as well as major adverse cardiac or cerebrovascular event. RESULTS: Patients with preoperative AF presented with more severe congestive heart failure (p = 0.03) and more often had significant tricuspid regurgitation (p = 0.01) preoperatively. They also had worse late survival (risk ratio [RR] for death = 1.5, p = 0.03) with 1-, 5-, and 7-year survival rates substantially reduced at 94%, 87%, and 50%, respectively, for those in AF versus 98%, 90%, and 61% for patients in sinus rhythm preoperatively. Individuals in AF had a greater probability of subsequent rhythm-related intervention (RR = 4.7, p = 0.0002), and more frequently developed congestive heart failure (25% vs 10%, p = 0.005) and stroke (16% vs 5%, p = 0.005). By multivariable analysis, preoperative AF was an independent predictor of late adverse cardiac and cerebrovascular events, but not late death. CONCLUSIONS: Performance of concomitant arrhythmia surgery in patients undergoing aortic valve surgery may reduce late morbidity; however, its potential impact on late mortality in this high-risk subset of patients remains unclear.

Aged↗
PubMed2006

Bicuspid aortic valve and ascending aortic aneurysm are not associated with germline or somatic homeobox NKX2-5 gene polymorphism in 19 patients.

BACKGROUND: Bicuspid aortic valve is the most common congenital anomaly, occurring in 1% to 2% of the population. It is the most common reason for aortic valve replacement, and such individuals are at significantly increased risk of aortic complications. Despite the clinical significance of bicuspid aortic valve, its genetic basis remains unclear. The homeobox gene NKX2-5 occupies a central position in the hierarchy of cardiac determinants, and mutations in this gene are associated with bicuspid aortic valve in mice. We therefore investigated the presence of mutations in NKX2-5 among patients with bicuspid aortic valve and associated aneurysm. METHODS: Germline DNA was extracted from peripheral blood leukocytes and somatic DNA from diseased aortic tissues of 19 patients with bicuspid aortic valve and associated aortic aneurysm. Three patients with trileaflet aortic valve and aneurysm served as control subjects. The entire NKX2-5 coding sequence, including intron-exon boundaries, was screened for mutation by means of polymerase chain reaction, followed by DNA sequencing. RESULTS: Direct sequencing revealed a change in somatic (aortic) DNA 239A-->G, leading to synonymous amino acid alteration of Glu21Glu in one patient with bicuspid aortic valve and 1 control subject. There were no other alterations detected in the coding regions of germline or somatic genes. A known polymorphic change in the 3' untranslated region adjacent to exon 2 was detected in both bicuspid aortic valve and control samples. Discrepancies between germline and somatic DNA sequences were observed. CONCLUSION: Our study fails to demonstrate an association between bicuspid aortic valve and NKX2-5 mutation, as has been seen in mice. Our findings support the importance of sequencing somatic, as well as germline, DNA.

Aortic Aneurysm, Thoracic↗
PubMed2006

The effect of adjuvant perfusion techniques on the incidence of paraplegia after repair of traumatic thoracic aortic transections.

OBJECTIVE: To analyze the effect of adjuvant perfusion techniques of the distal aorta on the outcome of traumatic thoracic aortic transections. PATIENTS AND METHODS: From 1973 to 2004, 72 patients (mean age, 39 years) with thoracic aortic transections arrived alive at the emergency department. Nineteen patients arrived in extremis and underwent emergency operations, 42 patients were stable and underwent diagnostic evaluation before surgery (4 patients experienced aortic rupture during evaluation), and 11 patients presented more than 24 hours after the accident. Sixteen patients died before aortic repair could be performed. Operative repair was possible in 53 patients (46 stable and 7 in extremis). Interposition graft was performed in 47 patients, and primary repair was performed in 6 patients. Morbidity, mortality, and paraplegia rate were analyzed. RESULTS: Patients in extremis had a mortality rate of 84% (16 of 19), stable patients had a mortality rate of 11% (4 of 38), patients who experienced rupture during evaluation had a mortality rate of 100% (4 of 4), and patients who underwent delayed operation had a mortality rate of 0% (0 of 11). The paraplegia rate with and without adjuvant distal aortic perfusion techniques was 2% (1 of 41 patients) and 33% (4 of 12 patients), respectively (P=.007). Mortality and paraplegia rates were 4% and 4% for partial bypass (n=24), 42% and 33% for the clamp and sew technique (n=12), 0% and 0% for Gott shunt (n=10), and 29% and 0% for full cardiopulmonary bypass (n=7), respectively. CONCLUSIONS: Although thoracic aortic transections remain a highly lethal injury, hemodynamically stable patients have a low operative mortality. Spinal cord injury is decreased by the use of adjuvant perfusion techniques that maintain distal aortic perfusion during cross-clamping of the aorta.

Adult↗