Do valve type and post-ballooning affect transprosthetic gradients in patients undergoing transcatheter aortic valve-in-valve procedure?

Introduction

Valve-in-Valve transcatheter aortic valve implantation (ViV-TAVI) is an appealing treatment option for patients with degenerated aortic bioprosthetic valves. However, high post-procedural transprosthetic gradients are very common after ViV-TAVI than after TAVI for native-valve aortic stenosis.

Aim

We sought to evaluate transprosthetic gradients (ΔP) and hemodynamic outcome in patients undergoing ViV-TAVI according to valve type and balloon post-dilation (balloon-expandable vs self-expandable with and without post-dilation).

Material and methods

We retrospectively analyzed 111 patients undergoing ViV-TAVI. A balloon-expandable valve was used in 35 patients (32%, Group 1), a self-expandable valve in 76 cases of which 39 (35%, Group 2) without balloon post-dilation and 37 (33%, Group 3) with balloon post-dilation. A comprehensive transthoracic echocardiography (TTE) was performed in all patients at baseline, at discharge and at 6-months follow-up.

Results

Successful ViV-TAVI was performed in 110 patients (99%). Baseline peak and mean ΔP, left ventricular volumes, ejection fraction, and pulmonary artery systolic pressure were similar among groups. A significant improvement in all echocardiographic parameters was observed in all groups over time (Table 1). In particular, a significant reduction in postprocedural gradients was observed at discharge and at 6-months follow-up compared to baseline in all groups. Immediately after ViV-TAVI procedure, the lowest value of mean ΔP was observed in Group 3 (12±7 mmHg) compared to both Group 1 (20±9 mmHg) and Group 2 (17±8 mmHg, p=0.001). This result was confirmed at 6-months follow-up (p=0.012). Rate of small valve size (≤23 mm) implanted was similar among groups (Group 1: 78%, Group 2: 60%, Group 3: 62%, p=0.123). Similar 1-year all-cause mortality was observed among groups (9%, 13%, 0%, respectively, p=0.135).

Conclusions

In patients with failed surgical aortic prosthesis, ViV-TAVI is an effective option and is associated with sustained improved hemodynamics in all patients. Anyway, the choice of prosthetic valve type and implantation technique are relevant on residual transprosthetic gradients and should be taken into account for a better long-term outcome.

Funding Acknowledgement

Type of funding sources: None.

Improving assessment of different flow state of aortic stenosis: implication for prognosis in patients undergoing transcatheter aortic valve replacement

Background

Low-flow low-gradient (LF-LG) aortic stenosis (AS) may occur with preserved or depressed left ventricular ejection fraction (EF), and both situations represent the most challenging subset of patients with AS to manage and generally have a poor prognosis with conservative therapy but a high operative mortality if treated surgically. Few and controversial data exist on the outcomes of these patients compared to normal-flow high-gradient (NF-HG) AS following transcatheter aortic valve replacement (TAVR).

Purpose

This study aims to better characterize patients with different transvalvular flow-gradient patterns undergoing TAVR and to examine the prognostic value of these flow state.

Methods

Overall, 1208 patients with severe symptomatic AS undergoing TAVR were categorized according to flow-gradient patterns as follow: 976 patients NF-HG (DPmean >40 mmHg), 107 paradoxical LF-LG (pLF-LG: DP mean <40 mmHg, EF >50%, and SVi <35 mL/m2), and 125 classical LF-LG (DP mean <40 mmHg, EF <50%, SVi <35 mL/m2).

Results

TAVR was feasible in all AS subtypes. When compared with NF-HG and pLF-LG, LF-LG had a worse symptomatic status (NYHA III–IV 86% vs 62% and 67%, respectively, p<0.001), a higher prevalence of eccentric hypertrophy (Figure 1, left), a higher level of LV global afterload reflected by a higher valvuloarterial impedance and a higher pulmonary pressure (Table). Valvular function after TAVR was excellent over time with respect to aortic pressure gradient (mean and peak) and aortic valve area regardless of flow state group. While intraoperative (p=0.935) and 30-day mortality (p=0.911) did not differ significantly among the 3 groups, LF-LG had a lower overall 5-year survival (LF-LG 50%, pLF-LG 65%, NF-HG 84%, p<0.001) (Figure 1, right). LF-LG AS was associated with a hazard ratio for 5-year mortality of 2.416 (95% CI: 1.658–3.520, p<0.001).

Conclusions

TAVR is an effective procedure in all patients with severe AS regardless of transvalvular flow-gradient patterns. However, special care should be given to characterized hemodynamic of AS, as patients with pLF-LG had similar survival rate than patients with NF-HG, whereas survival in LF-LG patients was 2-fold higher. Therefore, being able to identify patients less likely to improve after TAVR may help to guide treatment decision.

Funding Acknowledgement

Type of funding sources: None.

P330 A CASE OF SEVERE AORTIC STENOSIS IN A YOUNG PATIENT WITH BICUSPID AORTIC VALVE, FAMILIAL HYPERCHOLESTEROLEMIA AND CALCIFICATION AT THE SINOTUBULAR JUNCTION

Background

Familial hypercholesterolemia (FH) is a disorder characterized by elevated LDL–C and premature vascular calcifications. Aortic stenosis (AS) is the most frequent complication of bicuspid aortic valve (BAV), often requiring aortic valve replacement. Cardiac surgery in patients with severely calcified ascending aorta is challenging.

Case Presentation

A 28 year old male from Albania presented to the ED for dyspnea and low–threshold angina. The patient had family history for CAD and a sister with known FH treated with PCSK9–i. He had BAV, known hypercholesterolemia (max cholesterol 660 mg/dL), treated since 2015 with rosuvastatin plus ezetimibe, with reported irregular intake. He was treated with PCI and bioresorbable vascular scaffold on LAD coronary artery. He underwent surgical removal of limb xanthomas. At admission, the patient was asymptomatic at rest. Cardiac auscultatory findings included an ejection murmur in the aortic area. He presented upper and inferior eyelid xanthelasmas, bilateral calcaneal tendon thickening, elbows and knee xanthoma removal scars. Blood tests were unremarkable, except for lipid profile (LDL–C 443 mg/dL, HDL 36 mg/dL, TG 73 mg/dL). The echocardiography showed BAV, severe AS (Vmax 4,2 m/s, MPG 41 mmHg, AVA 0.46 cm2/m2), EF 60%. A coronary angiography excluded significant stenosis in the epicardial coronary vessels. An aortic CT scan showed sinotubular junction with preserved diameters and severe multiple parietal calcifications, ascending aorta with diffuse atheromatous disease. The patient underwent mechanical aortic valve replacement, ascending aorta thromboendarterectomy, non–coronary sinus enlargement patch, double CABG (SVG–OM, SVG–LAD) due to diffuse hypokinesia of the left ventricle after the interruption of extracorporeal circulation. At a 3–month outpatient re–evaluation, due to the unsatisfactory response to the regular intake of rosuvastatin plus ezetimibe (TC 309 mg/dL, TG 52 mg/dL, HDL 34 mg/dL, LDL–C 264 mg/dL), a PCSK9–i was prescribed. Genetic studies for FH are ongoing.

Discussion

This case underlines the importance of aortic evaluation before aortic valve replacement, even in young FH patients, in which severe aortic calcification can influence surgical approach.

Conclusion

We described the multidisciplinary management of a severe symptomatic AS in a young male with FH and sinotubular junction parietal calcifications, which represented a challenging substrate for valve replacement.

Prosthesis-patient mismatch after aortic valve in valve procedure: incidence, predictors and clinical outcomes

Funding Acknowledgements

Type of funding sources: None.

Background. Transcatheter aortic valve-in-valve (TAVI ViV) implantation is an appealing treatment option for patients with degenerated bioprostheses. However, elevated residual gradients after TAVI ViV procedure are very common. These are an unwanted effects of prosthesis-patient mismatch (PPM). Currently, the actual incidenceof PPM, its predictors and its clinical outcomes have not been completely investigated.

Purpose. The aims of this study was to investigate the incidence, predictors and clinical outcome of PPM and therefore of elevated gradients after TAVI ViV.

Methods. 75 patients (age 78 ± 9 years, 36 male), who underwent TAVI-ViV due to failed aortic biological valve (60 stented, 15 stentless), were enrolled. Mechanism of bioprosthetic valve failure was stenosis (34 cases, 45%), regurgitation (24 cases, 32%) or combination (17 cases, 23%). Elevated residual gradients were defined as a mean DP> 20 mmHg. PPM was identified by the indexed effective orifice area (EOAi) measured by echocardiography (moderate PPM if 0.65 < EOAi < 0.85 cm²/m²; severe PPM if EOAi < 0.6 cm²/m²).

Results. ViV TAVI was feasible in all patients, 33 patients (44%) were implanted with a balloon-expandable valve and 42 (56%) with a self-expandable valve. Post-procedural post-ballooning was performed in 16 out of 42 patients (38%) receiving a self-expandable valve. Post-operative mean DP> 20 mmHg was found in 35 patients (48%). Moderate PPM was found in 24 cases (33%) and severe PPM in 15 (20%). A logistic regression analyses identified small size of surgical prosthesis (size < 23 mm) [OR: 6.061(2.127-17.267), p = 0.001] and failed stented valve [OR: 20.727(2.522-170.364), p = 0.005] as independent predictors for the occurrence PPM. Interestingly PPM did not affect early and 1 years mortality (1 years mortality 1.3 %), while mortality was higher in pts with stentless prostheses (9%)

Conclusions. PPM is a frequent finding after ViV procedures. Despite elevated residual gradients, TAVI ViV resolved prosthetic dysfunction and PPM did not affect mortality.  Therefore, this procedure represents a promising new option for patients with failed biological prosthetic valves.

624 Is TAVI a useful procedure in paradoxical low flow-low gradient aortic stenosis? A long-term mortality study

Background

Clinical outcomes of patients with paradoxical low-flow, low-gradient aortic stenosis (PLF-LG) undergoing valve replacement are controversial. PLF-LG is a combination of a small aortic valve area (AVA < 1cm²), a preserved left ventricular (LV) ejection fraction (LVEF≥50%), and a ‘paradoxical’ low mean gradient due to the presence of low LV stroke volume (≤35 mL/m²). The low flow state is explained by the presence of a high afterload and pronounced LV concentric remodeling, with impaired LV filling. Surgical aortic valve replacement has been associated with very positive outcomes in normal-flow high-gradient (NF-HG) AS, whereas poorer outcomes has been reported in patients with PLF-LG AS.

Purpose

The aim of this study is to determine the clinical outcomes in patients with PLF-LG AS undergoing transcatheter aortic valve implantation (TAVI) compare to NF-HG patients.

Methods

A total of 624 patients (age 81 ± 7 years) with symptomatic severe AS and preserved LVEF who underwent TAVI, was enrolled and divided in 2 groups: group NF-HG included 554 patients (89%) and group PLF-LG including 70 patients (11%). At 1-year follow-up, death and clinical events were reported.

Results

TAVI was feasible in all patients. A significant reduction in mean aortic pressure gradient was observed after TAVI both in PLF-LG (baseline, 30 ± 6 mmHg; 1-year, 12 ± 4 mmHg; p < 0.001) and in NF-HG (baseline, 55 ± 12 mmHg; 1-year, 11 ± 4 mmHg; p < 0.001) together with an increase in AVA (PLF-LG: baseline, 0.73 ± 0.16 cm², 1-year: 1.82 ± 0.43 cm², p < 0.001; NF-HG: baseline, 0.66 ± 0.18 cm², 1-year: 1.84 ± 0.38cm², p < 0.001). Perioperative mortality at 30-days was similar in group NF-HG (17/554, 3%) and in group PLF-LG (2/70, 3%). Figure shows the survival curves up to 5 years follow-up according to the two groups. PLF-LG and HG-AS had similar survival rate throughout the long-term follow-up. Similarly, rehospitalization rate was not different in the two groups (PLF-LG: 12% vs NF-HG: 7%, p = 0.127).

Conclusions

Differently from surgical series, TAVI in PLF-LG AS is a useful procedure showing similar mortality and rehospitalization rates compared to NF-HG AS patients.

Abstract 624 Figure. Survival curve

P927Long-term mortality in patients with paradoxical low-flow low-gradient versus normal-flow high-gradient aortic stenosis undergoing transcatheter aortic valve implantation

Background

Controversial data exist on clinical outcomes of patients with paradoxical low-flow, low-gradient aortic stenosis (PLF-LG) undergoing valve replacement. This entity is a combination of a small aortic valve area (AVA<1cm2), a preserved left ventricular ejection fraction (LVEF≥50%), and a “paradoxical” low mean gradient due to the presence of low LV stroke volume (≤35 mL/m2). The low flow state is explained by the presence of a high afterload and pronounced LV concentric remodeling, with impaired LV filling. Currently, poorer outcomes have been reported after surgical aortic valve replacement in patients with PLF-LG AS compared with the normal-flow high-gradient (NF-HG) AS.

Purpose

The aim of this study was to determine the clinical outcomes in patients with PLF-LG AS undergoing transcatheter aortic valve implantation (TAVI) compare to NF-HG patients.

Methods

A total of 609 patients (age 81±6 years) with symptomatic severe AS and preserved LVEF who underwent TAVI, was enrolled and divided in two groups: group A included patients with NF-HG (542 patients) and group B including those with PLF-LG (66 patients). At 1-year follow-up, death and clinical events were reported.

Results

TAVI was feasible in all patients. A significant reduction in mean aortic pressure gradient was observed after TAVI both in PLF-LG (baseline, 30±5 mmHg; 1-year, 11±4 mmHg; p<0.001) and in NF-HG (baseline, 53±11 mmHg; 1-year, 12±4 mmHg; p<0.001) together with an increase in AVA (PLF-LG: baseline, 0.74±0.16 cm2, 1-year: 1.83±0.41 cm2, p<0.001; NF-HG: baseline, 0.65±0.16 cm2, 1-year: 1.84±0.35cm2, p<0.001). Perioperative mortality at 30-days was similar in group A (17/542, 3%) and in group B (2/66, 3%). Figure shows the survival curves up to 5 years follow-up according to the two groups. PLF-LG and HG-AS had similar survival rate throughout the long-term follow-up. Similarly, rehospitalization rate was not different in the two groups (PLF-LG: 12% vs NF-HG: 7%, p=0.121).

Kaplan-Meier analysis

Conclusions

Differently from surgical series, TAVI patients with PLF-LG AS had showed similar mortality and rehospitalization rates compared to NF-HG.

P5382Geometry and strain sensing dictate YAP-dependent evolution of human cardiac stromal cells toward myofibroblasts in the cardiosphere organoid model

Background

Cardiac stromal cells are the most abundant cell type present in the heart, where they have an important homeostatic function in matrix renewal and electromechanical coupling. We have shown that YAP transcription factor (a component of the Hippo pathway) is important for the proliferation of these cells and, potentially, pathologic cardiac matrix stiffening in heart failure.

Purpose

Given the role of Hippo pathway in cell mechanosensation, we assessed the conditions for activation of the YAP-dependent transcriptional pathway related to geometry/strain sensing using human “cardiosphere”-derived cells.

Methods

Human cardiospheres (C-Sp) and C-Sp-derived cells (CDCs) were obtained from fragments of atrial appendages of patients admitted for AoC bypass. C-Sps and CDCs were cultured using published methods. To analyze cell/nuclear geometry in 2D/3D culture, we employed an adapting thresholding algorithm allowing segmentation of cell membrane/nuclei shape and the relative abundance of nuclear/cytoplasmic fluorescence intensities from z-stacked confocal immunofluorescence images. Inhibitors of signaling cascades converging onto actin cytoskeleton polymerization or of YAP/TEADs interaction were used to assess YAP target genes transcription.

Results

Previous results showed stiffness sensitivity of YAP nuclear translocation process. Namely, CDCs plated onto stiff (E >50kPa) culture plates exhibited high ratios of nuclear/cytoplasmic YAP, as compared to cells plated on substrates with lower stiffness (E ∼ 10kPa). Analogously, cells with a stretched cytoplasm/nuclear shape in the border regions of the 3D organoids exhibited a higher YAP nuclear localization level and expression of fibrotic markers compared with cells with a more round geometry in the center of the spheres. To uncouple the cytoskeleton tensioning-dependent YAP nuclear shuttling, we treated CDCs plated onto stiff substrates with blebbistatin and Y27632. This showed a fully reversible YAP relocation from the nucleus to the cytoplasm and a reversion of canonical target genes (CYR61, ANKRD1 and CTGF) expression. In parallel, a “softening” process of the nucleus, likely due to release from cytoskeleton traction forces, was observed by confocal imaging along the cellular z-axis. Interestingly, use of Verteporfin, a drug directly interfering with the interaction of YAP/TAZ complex with TEADs DNA binding proteins showed reversion of pro-fibrotic YAP targets independent of high cytoskeleton tensioning.

Conclusions

These results establish, for the first time, a deterministic relationship between pro-pathologic evolution of human adult cardiac stromal cells and activation of mechanosensing-dependent pathways. They also provide quantitative criteria for interpreting fibrotic evolution of the heart based on modifications of myocardial architecture and mechanical compliance, as well as the ability of the cells to generate tension forces affecting the nuclear structure.

Distinct roles for PAR1- and PAR2-mediated vasomotor modulation in human arterial and venous conduits

BACKGROUND

Patency rates after coronary artery bypass grafting (CABG) are better if the internal mammary artery (IMA) is used rather than the greater saphenous vein (GSV), and may be related to the endothelial release of vasodilators antagonizing vascular contraction. It has recently been shown that a family of protease-activated receptors (PARs) modulate endothelium-dependent vasodilatation.

OBJECTIVE AND METHODS

The aim of this study was to evaluate the presence and functional role of protease-activated receptor 1 (PAR1) and protease-activated receptor 2 (PAR2) in mediating vascular tone in IMAs and GSVs from patients undergoing CABG by means of real time-PCR and isometric tension measurements.

RESULTS

PAR1 mRNA levels were higher than those of PAR2 mRNA in both vessels. A selective PAR2-activating peptide (PAR2-AP), SLIGKV-NH(2) (0.01-100 micromol L(-1)), failed to induce vasorelaxation in precontracted IMA and GSV rings, whereas the selective PAR1-AP, TFLLR-NH(2) (0.001 to 10 micromol L(-1)), caused greater endothelium-dependent relaxation in the IMAs (pD(2) values 7.25 +/- 0.6 vs. 7.86 +/- 0.42, P < 0.05; E(max) values 56.2 +/- 17.3% vs. 29.7 +/- 13.4%, P < 0.001). Preincubation with TNFalpha (3 nmol L(-1)) induced vasorelaxation in IMAs in response to PAR2-AP (P < 0.05 vs. non-stimulated vessels); the response to PAR1-AP was unchanged. The relaxation induced by both PAR-APs was NO- and endothelium-dependent.

CONCLUSION

These data show that functionally active PAR1 and PAR2 are present in IMAs and GSVs, and that inflammatory stimuli selectively enhance endothelium-dependent relaxation to PAR2-AP in IMAs.

Off-pump redo coronary artery bypass grafting: technical aspects and early results

BACKGROUND

Redo coronary artery bypass grafting (CABG) represents an high-risk surgical procedure, because of an increased incidence of perioperative death, myocardial infarction and stroke. Theoretically, the avoidance of cardiopulmonary bypass may reduce surgical traumatism and ameliorate early results.

MATERIALS AND METHODS

From January 1995 to May 2001, we performed 123 redo CABGs, of which 53 (44%) off-pump. Off-pump procedure represented respectively 90% of redo CABG in the period 2000-2001 versus 30% in the 1995-1999 period. The mean age was 66.4 years, males were 39 (73%). The mean 2D-echo ejection fraction was 56% and in 9 cases (17%) was less than 40%. Three operations (5.6%) were performed on an urgent base. The access was median sternotomy in all cases. The mean number of grafts per patient was 1.9 (1.7 in the period 1995-99 vs. 2.3 in the period 2000-01, p=0.01). In 20 cases (38%) we grafted the circumflex artery branches (19% in the period 1995-99 vs. 55.5% in the period 2000-01, p=0.015). Improvements in surgical techniques were achieved over time. The current operative strategy includes the use of deep traction stitches in the posterior pericardium and wall stabilizers to expose target vessels, coronary intraluminal shunts during construction of the anastomoses and continuous trans-esophageal echocardiographic monitoring. Urgent conversion to on-pump procedure was not required in any case.

RESULTS

We recorded no in-hospital death, one perioperative myocardial infarction (1.9%), one fifth postoperative day-stroke (1.9%) and 9 atrial fibrillations (17%). Mediastinal re-exploration for bleeding was performed in no one patient; 13 patients (24.5%) required postoperative blood transfusion. The mean length of postoperative stay was 7.5 days, ranging from 6 to 18 days.

CONCLUSIONS

In our experience off-pump redo CABG is a safe and effective alternative to on-pump procedure and now off-pump is our first choice-technique in redo CABG. A complete revascularization is technically feasible with a low incidence of perioperative complications.

Determinants of early and late outcome after surgery for type A aortic dissection

The aim of this study was to identify the most important variables associated with early and late mortality in patients operated on for type A aortic dissection over a 15-year period. From January 1984 to March 1999, 110 patients underwent surgery for type A aortic dissection. The 88.1% of patients had an acute type A dissection (AD) and 11.8% had a chronic dissection (CD). Cardiac tamponade and shock occurred in 21.8% and 14.5% of the patients, respectively. The location of the primary intimal tear was in the ascending aorta in 70.9% of cases, in the arch in 17.2%, and in the descending aorta in 7.2%. Univariate and multivariate analyses were conducted to identify non-embolic variables independently correlated to in-hospital death. Kaplan-Meier and Cox regression analyses and hazard function for death risk were used to analyze factors influencing overall and surgical survival. The overall in-hospital mortality rate was 20.9% (23/110 patients), being 9% for CD and 21.6% for AD. Emergent procedures had an in-hospital mortality rate of 47.6%, whereas nonemergent operations had an in-hospital mortality rate of 13.7% (p < 0.01). Univariate analysis revealed 41 preoperative and operative variables, including age (years), age >70 years, remote myocardial infarction, cerebrovascular dysfunction, diabetes, preoperative renal failure, shock, cardiopulmonary bypass time (minutes), emergency operation, as factors associated to in-hospital death (p < 0.05). Stepwise logistic regression analysis for in-hospital death selected as independent predicting variables (p < 0.05) remote myocardial infarction [p = 0.006, odds ratio (OR) = 1.9], preoperative renal failure (p = 0.031; OR = 0.8), shock (p = 0.001; OR = 3.1), and age >70 years (p = 0.007; OR = 1.7). Follow-up ranged from 9 to 172 months (median 78 months), with Kaplan-Meier survivals for all the patients and hospital survivors of 42% and 54% at 10 years, respectively. Cox regression analysis has identified postoperative stroke [relative risk (RR) = 3.7; p = 0.012), intimal tear in the aortic arch (RR = 2.3; p = 0.036), and postoperative renal failure (RR = 4.5; p = 0.007) as independent predictors of reduced survival at follow-up. When this kind of analysis was performed on hospital survivors only, preoperative renal dysfunction (RR = 1; p = 0.013), reoperation (RR = 1.7;p = 0.004) and intimal tear in the aortic arch (RR = 1.2; p = 0.002) emerged as risk factors. The actuarial freedom from reoperation was 85.4% at 5 years. Multiple factors still influence early and late survival after surgery for type A aortic dissection. Preoperative renal impairment both affects early and late outcome. Early postoperative course affects late outcome in hospital survivors. The presence of the intimal tear in the aortic arch has a negative impact on late survival.

[Myocarcial revascularisation without extracorporeal circulation: current indications, surgical technique and results]

BACKGROUND

This study was undertaken to assess our experience of the evolution, over time, of beating heart surgery in the Cardiologic Center Foundation Monzino.

METHODS

From March 1995 to June 2000, 506 patients underwent myocardial revascularization on beating heart: 313 until May 1999, and 193 between June 1999 and June 2000, after the advent of coronary artery stabilizers and shunts, to keep the surgical field bloodless, with minimal motion and continuous myocardial perfusion. Surgical accesss was via a median sternotomy for 408 cases and via a left anterior thoracotomy for 98 cases.

RESULTS

The indications by choice increased, from I to II period, from 61% to 83% with special situations in which patients had three-vessel coronary artery disease raised from 33% to 50%, concerning also bypass grafts performed on circumflex artery and right coronary increased. Postoperative mortality in hospital decreased from 1.3% to 0.5% and perioperative IMA (acute myocardial infarction) from 3.8% to 0.5% in patients undertaken to median thoracotomy. Hospital stay decreased from 8 to 7 days about [no significant differences with patients who underwent CPB (cardiopulmonary bypass)]; in patients who underwent to MTS (left anterior minithoracotomy) there was no deaths, IMA decreased from 3.9% to 0% and hospital stay from 6 to 5 days. Grafts patency increased from 92.3% to 100%.

CONCLUSIONS

To perform completed revascularisations is possible now even on the beating heart, and also to make precise anastomosis as on pump CABG, in a reproducible and easy way. The beating heart procedure, that is also more economical, might be expanded to all patients, not only high risk patients.

Endovascular repair of latrogenic subclavian artery perforations using the Hemobahn stent-graft

PURPOSE

To report the use of a new self-expanding endograft for percutaneous treatment of iatrogenic subclavian artery perforations.

CASE REPORTS

The subclavian artery of 2 patients was inadvertently cannulated during percutaneous attempts to implant a permanent pacemaker in one and catheterize the subclavian vein in the other. Because both patients had serious comorbidities, endovascular repair of the subclavian perforations was performed using the Hemobahn endograft, a nitinol stent covered internally with expanded polytetrafluoroethylene. The endoprostheses were successfully deployed via an ipsilateral brachial artery access. No signs of endograft occlusion, migration, deformation, or fracture have been observed during follow-up at 12 and 10 months, respectively, in these patients.

CONCLUSIONS

The Hemobahn stent-graft appears well suited to repairing subclavian artery injuries. Longer follow-up will determine if the design of this endograft will resist compression in this vascular location.

A preoperative index of mortality for patients undergoing surgery of type A aortic dissection

BACKGROUND

The aim of this study was to identify and stratify the most important preoperative factors for in-hospital death after surgery for type A aortic dissection.

METHODS

From January 1985 to June 1998, 108 patients underwent surgery for type A aortic dissection. 89.9% of the patients had an acute type A dissection (AD), whereas 11.1% had a chronic dissection (CD). Cardiac tamponade and shock occurred in 22% and 14.8% of the patients, respectively. The location of the primary intimal tear was in the ascending aorta in 71.2% of the cases, in the arch in 16.6% and in the descending aorta in 7.4%. Univariate and multivariate analyses were conducted to identify non-embolic variables independently correlated to in-hospital death. A predictive model of in-hospital mortality was then constructed by means of a mathematical method with the variables selected from logistic regression analysis.

RESULTS

The overall in-hospital mortality rate was 20.3% (22/108 patients), being 9% for CD and 21.6% for AD. Emergent procedures had an in-hospital mortality rate of 47.6%, whereas non-emergent operations had an in-hospital mortality rate of 13.7% (p<0.01). Univariate analysis revealed among 39 preoperative and operative variables, age (years), age >70 years, remote myocardial infarction, cerebrovascular dysfunction, diabetes, preoperative renal failure, shock, cardiopulmonary bypass time (minutes), emergency operation as factors associated to in-hospital death (p<0.05). Stepwise logistic regression analysis selected as independent predicting variables (p<0.05), remote myocardial infarction (p=0.006), preoperative renal failure (p=0.032), shock (p=0.001), age >70 years (p=0.007). Finally, a probability table of death risk was obtained with the logistic regression coefficients. The lower death probability (10.6%) was calculated in absence of risk variables; the higher one in presence of all of them (79.7%). Between these extremes, a total of 64 combinations of death risk were obtained.

CONCLUSIONS

Increasing age, shock, coronary artery disease and renal failure are variously associated to a high risk of in-hospital death after surgical correction of type A aortic dissection. This predictive model of death probability allows to collocate preoperatively patients with type A aortic dissection at different levels of risk for in-hospital death.

Adult cardiac surgery outcomes: role of the pump type

OBJECTIVE

This study was carried out to evaluate whether the type of pump used for cardiopulmonary bypass (CPB; roller vs. centrifugal) can affect mortality or the neurological outcomes of adult cardiac surgery patients.

METHODS

Between 1994 and June 1999, 4000 consecutive patients underwent coronary and/or valve surgery at our hospital; of these, 2213 (55.3%) underwent surgery with centrifugal pump use, while 1787 (44.7%) were operated on with a roller pump. The effect of the type of the pump and of 36 preoperative and intraoperative risk factors for perioperative death, permanent neurological deficit and coma were assessed using univariate and multivariate analyses.

RESULTS

The overall in-hospital mortality rate was 2.2% (88/4000), permanent neurological deficit occurred in 2.0% (81/4000) of patients, and coma in 1.3% (52/4000). There was no difference in hospital mortality between patients operated with the use of centrifugal pumps and those operated with roller pumps (50/2213 (2.3%) vs. 38/1787 (2.1%); P=0.86). On the other hand, patients who underwent surgery with centrifugal pumps had lower permanent neurological deficit (34/2213, (1.5%) vs. 47/1787 (2.6%); P=0.020) and coma (20/2213 (0.9%) vs. 32/1787 (1.8%); P=0.020) rates than patients operated with roller pumps. Multivariate analysis showed CPB time, previous TIA and age as risk factors for permanent neurological deficit, while centrifugal pump use emerged as protective. Multivariate risk factors for coma were CPB time, previous vascular surgery and age, while centrifugal pump use was protective.

CONCLUSIONS

Centrifugal pump use is associated with a reduced rate of major neurological complications in adult cardiac surgery, although this is not paralleled by a decrease in in-hospital mortality.

Nonembolic predictors of stroke risk in coronary artery bypass patients

The aim of this study was to identify and stratify the most important nonembolic risk factors for stroke after coronary bypass grafting. From June 1994 to June 1997 a series of 1532 patients (pts) underwent isolated myocardial revascularization on cardiopulmonary bypass (CPB). A retrospective chart review selected 1417 pts in whom the presence of aortic calcification or left ventricular mural thrombi was not detectable by echocardiogram, angiogram, and intraoperative records. Univariate and multivariate analyses were conducted to identify nonembolic variables independently correlated to postoperative stroke. A predictive model of stroke probability was then constructed by means of a mathematic method with the variables selected from logistic regression analyses. The global incidence of stroke was 1.8%. Univariate analysis revealed that, among 29 preoperative and operative variables, age, vasculopathy, emergency operation, previous cerebrovascular accident (CVA), CPB, and aortic cross-clamping times were factors strongly associated with postoperative stroke (p < 0.01). A first logistic regression analysis (LRA) selected as independent predicting variables (p < 0.05) age [odds ratio (OR) 1.07/year], vasculopathy (OR 4), previous CVA (OR 7.2), CPB time (OR 1/year), and emergency operation (OR 4.2). In a second stepwise LRA, age and CPB time were subdivided into cohorts as follows: age </= 65 years, > 65 but < 75 years, >/= 75 years; CPB time </= 120 minutes, > 120 but < 180 minutes, >/= 180 minutes. Both age >/= 75 years (p = 0.024; OR 3.3) and CPB time >/= 180 minutes (p = 0.002; OR 4.2), were found to be predictors of postoperative neurologic damage. Finally, a probability table of stroke risk was obtained with the logistic regression coefficients. A lower stroke probability (0.7%) was calculated in the absence of risk variables and a higher one in the presence of all of them (83.3%). Between these extremes, a total of 158 combinations of stroke probabilities were obtained. We concluded that previous CVA, vasculopathy, emergency operation, and age > 75 years are variously associated with a high risk of nonembolic stroke after myocardial revascularization. A duration of CPB longer than 3 hours strongly increases the probability of neurologic damage in the presence of the aforementioned variables.

Quick, simple clamping technique in descending thoracic aortic aneurysm repair

BACKGROUND

Although significant advances have been made in the surgical treatment of diseases affecting the descending thoracic aorta, paraplegia remains a devastating complication. We propose the quick, simple clamping technique to prevent spinal cord ischemic injury.

METHODS

From 1983 to 1998, 143 patients had descending thoracic aorta aneurysm repair. We divided the patients into the following three groups according to the surgical technique used: selective atriodistal bypass was used in group 1 (66 patients); simple clamping technique in group 2 (28 patients); and quick simple clamping technique in group 3 (49 patients). Mean aortic cross clamp time was 39+/-13 minutes in group 1, 37+/-11 minutes in group 2, and 17+/-6 minutes in group 3 (p<0.01 group 3 versus group 1 and group 2).

RESULTS

The overall incidence of paraplegia was 4.8% (7 patients), 4.5% (3 patients) in group 1, 14.3% (4 patients) in group 2, and 0 in group 3 (p<0.05 group 3 versus group 2). The overall in-hospital mortality rate was 5.5%. Multivariate logistic regression analysis showed a powerful effect of aortic cross-clamping time as risk factor for both paraplegia (p<0.008), with an odds ratio of 1.03 per minute, and in-hospital mortality (p<0.001), with an odds ratio of 2.5 per minute. The mean follow-up time was 65 months with a lower overall mortality rate in group 3 than in group 1 and group 2 (p<0.05).

CONCLUSION

In descending thoracic aortic aneurysm repair, spinal cord perfusion can be maintained adequately without reimplantation of segmental vessels or use of atriodistal bypass when the aortic cross-clamp time is short (<15 to 20 minutes).

Video-assisted minimally invasive coronary bypass surgery without cardiopulmonary bypass

BACKGROUND

There is a growing interest in cardiac surgery towards minimally invasive approach to coronary bypass operations without cardiopulmonary bypass.

PATIENTS AND METHODS

From March 1995 to March 1997, 41 patients underwent a single left internal mammary artery (LIMA) to the left anterior descending artery (LAD) coronary grafting without cardiopulmonary bypass through a small left anterior thoracotomy (MIDCABG). The mean age was 61.2+/-8.7 years (range 43-77 years), 28 patients. were male (68.2%) and the redo rate was 4.8% (2/41). In all patients the coronary artery disease involved the LAD, which was occluded in seven patients (17.1%). Thirty-eight patients (96.2%) selected for MIDCABG had a monovascular disease on LAD not suitable for percutaneous coronary angioplasty; two (4.8%) a bivascular disease, and one (2.4%) a trivascular disease. Skin incision was performed in the 4th anterior intercostal space from the left parasternal line for a 10.5 cm length on average. The LIMA harvesting was partially video-assisted by thoracoscopy.

RESULTS

The LAD temporary occlusion was achieved with two double 5/0 polypropilene round-LAD sutures. The mean LAD ischemic time was 22+/-8 min (range 4-35 min). No thoracotomy procedure was changed into a sternotomy approach. We had one (2.4%) perioperative AMI; two patients (4.8%) were reoperated for bleeding. All patients underwent a postoperative angiographic reinvestigation within 1 month after surgery. All anastomoses were perfectly patent but two (4.8%). One patient was reoperated via a sternotomy access recycling the LIMA graft, the other one underwent successful PTCA. All patients also underwent an early and mid-term (6 months after surgery) echo-Doppler study of the LIMA flow and patency. At follow-up, performed at a mean of 8.7 months (range 1-23) after discharge, all patients were alive; no one experienced recurrence of angina. All patients also performed a mid-term negative treadmill stress test.

CONCLUSIONS

MIDCABG is, in selected patients, reliable and safe, and offers encouraging early and mid-term clinical results.

[Surgery of the ascending aorta: the 1984-1995 experience of the cardiac surgery teaching unit in the University of Milan. Multivariate analysis of its risk factors for hospital mortality and reduced long-term survival]

Between 1984 and 1995, 183 patients underwent an ascending aorta procedure at our institution. Their mean age was 60 +/- 12.3 years; 116 (63.4%) patients were male, 35 (19.1%) had a history of congestive heart failure, 72 (39.3%) presented acute type A dissection, 23 (12.6%) were redos and 63 (34.4%) were operated on an emergency basis. In-hospital mortality was 10% (12/120) in elective procedures and 36.5% (23/63) in emergency operations (p < 0.0001). Multivariate stepwise logistic regression analysis identified cardiopulmonary by-pass time, emergency operation, arch replacement and the need for femoral vein cannulation at surgery as independent predictors of in-hospital death. Mean follow-up time was 54 +/- 30 months (median 50 months), with a Kaplan-Meier survival of 69 +/- 4% and of 60 +/- 5% at 5 and 7 years, respectively. Cox regression analysis identified arch replacement, perioperative myocardial infarction, preoperative NYHA class, acute type A aortic dissection, the need for femoral vein cannulation at intervention and redo operations as independent predictors of reduced survival at follow-up. When this kind of analysis was performed on hospital survivors only, postoperative tracheostomy, reexploration for bleeding, and the occurrence of postoperative ventricular arrhythmias emerged as risk factors. In conclusion, multiple factors affect both early and long-term outcome following ascending aorta surgery. Preoperative clinical status of patients, priority of surgery and aortic dissection are the main determinants of the short-term results. Otherwise, in hospital survivors, the main determinant for long-term outcome seems to be the immediate postoperative course.

Early and late results of ascending aorta surgery: risk factors for early and late outcome

This study was designed to evaluate risk factors for in-hospital mortality and midterm survival in patients undergoing ascending aorta surgery at a single institution during an 11-year period. Between 1984 and 1994 a total of 158 patients underwent an ascending aorta procedure at our institution. Their mean age was 59.6 +/- 12.3; 115 (73%) were male, 33 (21%) had a history of congestive heart failure, 61 (39%) had an acute type A dissection, 21 (13%) underwent redo operations, and 55 (35%) were operated on an emergency basis. In-hospital mortality was 9.7% (10/103) for elective procedures and 36.4% (20/55) for emergency operations (p < 0.0001). Multivariable stepwise logistic regression analysis identified the cardiopulmonary bypass time [odds ratio (OR) = 1.01/min, p = 0.0021], emergency operation (OR = 2.27, p = 0.0022), arch replacement (OR = 2.71, p = 0.0067), and the need of femoral vein cannulation at intervention (OR = 1.89, p = 0.0375) as independent predictors of in-hospital death. When this kind of analysis was performed, evaluating only the variables known before surgery, acute type A dissection (OR = 2.21, p = 0.0009) and preoperative NYHA class (OR = 1.88 per class, p = 0.0290) were independent risk factors for in-hospital death. Follow-up ranged from 10 to 126 months (median 42 months), with Kaplan-Meier survivals of 69 +/- 4%, and 60 +/- 5% at 5 and 7 years, respectively; survival rates for hospital survivors were 85 +/- 4% and 67 +/- 7% at 5 and 7 years, respectively. Cox regression analysis has identified arch replacement [relative risk (RR) = 2.48, p < 0.0001], perioperative myocardial infarction (RR = 2.44, p = 0.0003), preoperative NYHA class (RR = 1.97 per class, p = 0.0009), acute type A aortic dissection (RR = 1.44, p = 0.0238), the need of femoral vein cannulation at intervention (RR = 1.55, p = 0.0332), and redo operation (RR = 1.44, p = 0.0851) as independent predictors of reduced survival at follow-up. When this kind of analysis was performed on hospital survivors only, postoperative tracheostomy (p = 0.0003, RR = 3.42), reexploration for bleeding (p = 0.0003, RR = 3.77), and the occurrence of postoperative ventricular arrhythmias (p = 0.0007, RR = 2.45) emerged as risk factors. Multiple factors affect the early and late outcome after ascending aorta surgery; our data suggest that the preoperative clinical status of the patients and the priority of surgery and aortic dissection are the main determinants of the early results; on the other hand, the early postoperative course is the main determinant of the late outcome of hospital survivors.

Non-invasive evaluation of right gastroepiploic artery with colour Doppler echography

The right gastroepiploic artery has been increasingly used as a coronary bypass graft. Short- and mid-term patency rates support the supposition that the right gastroepiploic artery is a satisfactory bypass conduit. However, conclusive angiographic data on long-term patency rates are still lacking. An echo-colour Doppler method was used to detect patency of the right gastroepiploic artery grafts through an upper abdominal approach. A group of 24 patients with a right gastroepiploic artery graft to the right or posterior descending coronary artery, all of whom also had a postoperative angiographic study which showed 100% patency of the graft were used as a reference group. A second group of 89 patients was also investigated only with echo-colour Doppler during the postoperative period (mean 8.0 (range 1-48) months). A patent right gastroepiploic artery graft showed a biphasic velocity pattern. Systolic peak velocity ranged from 8 to 26 cm and diastolic peak velocity from 4 to 13 cm. The right gastroepiploic artery diameter ranged from 1.7 to 2.4 mm and flow from 10.2 to 58.8 ml. Among the second group were three patients who had, at their echo-colour Doppler examination, a possible occlusion of the right gastroepiploic artery graft; an angiographic study was conducted and the graft closure confirmed in all cases. Serial echo-colour Doppler evaluation of the right gastroepiploic artery blood flow pattern and diameter is a non-invasive and safe method to check the patency and flow capacity of the artery graft in follow-up studies.

[Surgical therapy for prosthetic infections of the thoracic aorta. Conservative approach]

The prosthetic graft infection of the thoracic aorta is a dreaded complication and it is associated with a high mortality rate. There is not substantial agreement in literature about how to manage a vascular graft infection, except for local anti-septic irrigation with a systemic antibiotic therapy. The main point of discussion is if it is mandatory to remove or not the infected thoracic aorta prosthesis: some authors prefer to eliminate all the thoracic aortic prostheses which may be infected, while others propose graft removal only when the sutures lines are involved. In this paper we report our experience on the conservative management of infected thoracic aorta prostheses using a local antiseptic irrigation, a perigraft debridement and leaving the original graft "in situ" when there is evidence of graft damage especially or involvement of the sutures lines. This approach has been performed in three patients: two had an infected aortic arch prosthesis, while one had a descending thoracic aorta prosthesis infection.

Surgery of descending thoracic aortic aneurysms with centrifugal pump support

Fifty-five patients with descending thoracic aortic aneurysms were operated upon between October 1987 and October 1994. All patients were supported by a centrifugal pump during operation. The mean(s.d.) duration of cross-clamping was 39(13) min. In order to evaluate the efficacy of the centrifugal pump, haemodynamic and metabolic measurements were made on four occasions (before cross-clamping, immediately after cross-clamping and before cross-clamp removal) and again after cross-clamp removal. The haemodynamic data remained stable throughout the procedure: central venous pressure (15(4.6) versus 16(4.8) versus 16(4.6) versus 15(4.6) mmHg; P = n.s.), pulmonary artery pressure (25(6.2) versus 24(5.1) versus 22(5.3) versus 23(4.4) mmHg; P = n.s.), radial systolic pressure (119(19.9) versus 116(25.2) versus 111(25.9) versus 111(20.7) mmHg; P = n.s.) and heart rate (75(12.6) versus 77(14) versus 76(15.6) versus 78(16) beats/min; P = n.s.). The acid-base status deteriorated slowly during surgery. Values before and after cross-clamping were: pH (7.42 (0.04) versus 7.37(0.06); P < 0.05), base excess (-0.67(2.20) versus -3.70(2.50); P < 0.05) and bicarbonates (24(8.9) versus 20(1.9); P < 0.05). The cerebrospinal fluid pressure remained constant: 20(5.7) versus 19(5.9) versus 18(5) versus 19(5) mmHg; P = n.s. Renal function, measured before, and at 1, 3 and 7 days after the operation also remained stable (creatinine: 1.1(0.4) versus 1.2(0.4) versus 1.2(0.4) versus 1.2(0.4); P = n.s.; blood urea nitrogen: 46(18.7) versus 46(18.6) versus 51(24.9) versus 55(27.9); P = n.s.). Step-wise multiple linear regression comparing cerebrospinal fluid pressure against haemodynamic and metabolic data showed that during aortic cross-clamping there was a significant relationship between central venous pressure (P < 0.0013) and arterial pH (P < 0.0148), while before and after cross-clamping multivariate analysis showed a relationship only between central venous pressure and cerebrospinal fluid pressure (P < 0.0035). The results confirm that centrifugal pump support is effective in stabilizing haemodynamics and protecting the kidney during thoracoabdominal aneurysm repair.

Myocardial revascularization procedures on multisegment diseased left anterior descending artery: endarterectomy or multiple sequential anastomoses (jumping)?

Complete revascularization is the primary goal in coronary surgery because of its superior long term results. However, in some patients the extent of the coronary artery disease is such that the usual coronary bypass technique may not allow to perform a complete myocardial surgical revascularization and, consequently, a satisfactory myocardial perfusion: so complementary revascularization techniques may become mandatory, especially when the diseased vessel is LAD or its branches. As a consequence, alternative procedures should be undertaken: coronary endarterectomy (EA) and multiple sequential anastomoses on a single vessel (jump), which guidelines are actually somehow controversial. Between January, 1989, and May, 1992, 53 patients underwent a myocardial revascularization procedure on LAD system unsuitable for single distal bypass; of them 35 (66%) underwent coronary endarterectomy, while in 18 (34%) multiple sequential anastomoses (jumping) were performed on the same vessel. About preoperative variables, average NYHA class (2.7 jump vs 2.1 EA group, p < 0.05), the history of more than 1 myocardial infarction (22.2% jump vs 2.9% EA, p < 0.04) and the presence of preoperative nitrates e.v (33.3% vs 8.6%, p < 0.04) were statistically higher in the jump group, suggesting a more unstable clinical status, while other clinical echocardiographic and catheterization features were not statistically different. For what operative and postoperative features are concerned, the number of anastomoses performed was statistically higher in the jump group, as exasperated (3.8 vs 2.7, p < 0.002) while perfusion (138 vs 141 min) and crossclamp time (103 vs 106 min) were similar. Furthermore we found a statistically lower incidence of perioperative myocardial infarction (0% jump is 22.8% EA group, p < 0.04); the postperfusion inotropic drugs requirement (22.2% vs 37.1%), the need of an intraaortic counterpulsation (0% vs 2.9%) and the in-hospital mortality (0% vs 5.7%) were lower in the jumping group too, also if they didn't reach statistical significance. Our experience suggest, also with the limits imposed by a retrospective case review and by a low number of cases reported, that myocardial revascularization of a multisegment diseased LAD system may be safely performed with the jumping technique with a low incidence of postoperative complications: it should be the first choice technique when conventional revascularization procedures are not enough to achieve complete myocardial revascularization. We advocate the use of EA technique only in that cases characterized by a diffuse atherosclerotic core and a well delimited plane of dissection, associated to a very poor runoff, which really excludes any chance to multiple anastomoses.

Straddling endoventricular pericardial patch in mitral valve repair with the sliding leaflet technique

Calcification of the mitral annulus is always a technical complication in mitral surgery and standard procedures are often difficult to perform; mitral valve replacement can be dangerous with a high risk of perioperative heart rupture, and reconstructive surgery is often contraindicated. Nevertheless in this case of posterior leaflet prolapse with annular calcification valve repair was performed, after complete calcium debridement causing annulus disruption and atrio-ventricular discontinuity, by means of a straddling atrio-ventricular pericardial patch and the sliding leaflet technique.

Pedicled arterial grafts in coronary surgery: postoperative echo color-Doppler study

In 1994 a mid-term postoperative echo color-Doppler ultrasound was performed to check the pedicled arterial conduits used in coronary surgery, such as the left and right internal mammary arteries (LIMA, RIMA) and the right gastroepiploic artery (RGEA). This evaluation was made in 31 patients with a previous nonemergent complete arterial myocardial revascularization. The pedicled arterial grafts studied were 71 (31 LIMA, 15 RIMA and 25 RGEA). The Doppler spectrum (combined systolic/diastolic waveform), the diameter and the flow of every arterial graft was always identified (100% of detection) and there was a statistical significative difference between mean RGEA flow versus mean LIMA and RIMA flow (p<0.05). All the conduits studied were characterized by a good diastolic and end-diastolic velocity, evidence of normal graft patency. The postoperative angiogram of the LIMA, RIMA and RGEA conduits was performed in 27/31 (87.1%) patients and it showed 100% patency of arterial grafts used and of anastomoses. The echo color-Doppler data were compared to postoperative angiographic results. The echo color-Doppler imaging of the pedicled arterial grafts used in coronary surgery seems to be a promising technique for the postoperative serial assessment of the LIMA, RIMA and RGEA conduit function, because it is noninvasive, safe, easy, quick to perform and the preliminary results of echo color-Doppler ultrasound versus angiography are satisfactory.

Descending thoracic aorta aneurysmectomy: left-left centrifugal pump versus simple clamping technique

Forty-six patients who had had an elective repair of a descending thoracic aortic aneurysm were reviewed, in order to investigate the efficacy of support by a centrifugal pump on distal organ perfusion and spinal cord protection during cross-clamping of the thoracic aorta. Two concurrent groups were analysed: 36 patients (78%) were supported by left atriofemoral arterial bypass with a centrifugal pump and 10 (22%) had no distal circulatory support. No patient was fully heparinized. The demographic data and preoperative characteristics of the groups, including location and type of aneurysm, were similar. The mean(s.d.) duration of cross-clamping was 37.8 (16) min in the centrifugal pump group and 42.3(21) min in the simple clamping group. Preoperative haemodynamic and laboratory data were similar in both groups. During cross-clamping, parameters of pH and blood urea varied but were better in the centrifugal pump group; changes from pre-intervention to early aortic cross-clamping time were not significant (pH, P < 0.0006; bases, P < 0.0003). Differences in creatinine values were caused mainly by the change from pre-intervention to the first postoperative day (P < 0.03); this continued throughout the hospital stay. The cerebrospinal fluid pressure measurement indicated a significant difference in time change (P < 0.0001) and mean level over time (P < 0.0002): levels were significantly lower in the centrifugal pump group throughout aortic cross-clamping. Three patients in the simple clamping group and none in the centrifugal pump group (P < 0.02) required cerebrospinal fluid drainage.(ABSTRACT TRUNCATED AT 250 WORDS)

Aortic arch surgery: pros and cons of selective cerebral perfusion. A multivariable analysis for cerebral injury during hypothermic circulatory arrest

Thirty-five consecutive patients with aortic arch aneurysm who required surgical reconstruction were operated on with the aid of extracorporeal circulation between February 1985 and December 1993. Nineteen patients (54.3%) were treated with hypothermic circulatory arrest (HCA) (Group A) and 16 (45.7%) (Group B) with HCA and selective cerebral perfusion (SCP) through the carotid arteries. Preoperative characteristics didn't show any significant differences between the two groups: mean age was 58.7 +/- 12 vs 62.1 +/- 7, p = ns, male sex 73.6% vs 75%, p = ns; atherosclerotic aneurysms were 57.8% vs 43.7%, p = ns; Type A dissections 42.2% vs 56.3%, p = ns and emergency operation were 68.4% vs 43.7%, p = ns in Groups A and B respectively. For SCP, blood was infused initially at a rate of 200-300 ml/min, maintaining the 30-40% of cerebral blood flow in normothermia, successively, with the aid of transcranial Doppler sonography (TDS) SCP-flow was improved to 500-1000 ml/min. The MHz pulsed TDS was used to measure the middle cerebral artery flow velocity in deep hypothermia before the arrest, in order to adjust the SCP flow during the HCA. In all patients we used open aortic anastomosis; in two cases an extraanatomical ascending-descending aorta was required, and in other two the "elephant trunk" technique was used in case of combined aortic arch and descending aneurysms. The HCA times were similar in the two groups 47.5 +/- 22 vs 47.7 +/- 78, p = ns. Early deaths occurred in 5 patients of the Group A (26.3%) and in 3 patients of the group B (18.7%), p = ns.(ABSTRACT TRUNCATED AT 250 WORDS)

False hydatic aneurysm of the thoracic aorta

In this article we report the successful treatment of a lower descending thoracic aorta hydatidosis that mimicked a posterior saccular aneurysm; surgical excision was performed and the aorta was repaired with a prosthetic Dacron patch. At a 26-month follow-up, the patient is alive and conducting a normal life. Discussion about the management of this rare case also is given.

Composite valve graft replacement of the ascending aorta and the aortic valve by a modified button technique: the influence of aortic pathology on early mortality and late survival

The risk factors for in-hospital mortality and mid-term survival in patients undergoing composite graft replacement of the aortic root with reimplant or coronary arteries by a modified button technique were evaluated with special emphasis on the underlying aortic pathology. Between 1985 and 1993 74 patients underwent replacement of the ascending aorta and the aortic valve following a modified button technique. The patients were divided into three groups according to aortic pathology: annuloaortic ectasia (43.58%), type A dissection (18.24%), and miscellaneous (13.18%). In-hospital mortality rates were 4.7%, 33.3% and 23.1%, respectively (P = 0.011). Univariate analysis showed that aortic pathology, NYHA class, emergency operation, redo operation, acute aortic dissection, preoperative cardiogenic shock, preoperative cardiac tamponade, longer cardiopulmonary bypass (CPB) and aortic cross-clamp times, and the need of femoral vein or femoral artery cannulation at intervention had univariate influence on in-hospital mortality. Multivariable stepwise logistic regression analysis identified CPB time odds ratio (OR) = 1.021/min, P = 0.007), the need of femoral vein cannulation at intervention (OR= 4.85, P = 0.008) and preoperative cardiac tamponade (OR = 3.11, P = 0.07) as independent predictors of in-hospital death. Follow-up ranged from 1 to 98 months (mean 39 +/- 30 months) with an actuarial survival rate of 75 +/- 9%, 52 +/- 13% and 67 +/- 14% at 5 years in annuloaortic ectasia, type A dissection, and miscellaneous patients, respectively (P = 0.18); when survival was evaluated in hospital survivors only, Kaplan-Meier survival rates were 77 +/- 9%, 79 +/- 14% and 89 +/- 10% at 5 years (P = 0.87). Comparing survival of annuloaortic ectasia patients (5-year survival 75 +/- 9%) versus survival of all other patients pooled together (5-year survival 55 +/- 11%), there was a statistically significant difference (P < 0.05); such a difference was no longer significant when comparing hospital survivors alone (5-year survival rate 77 +/- 9% annuloaortic ectasia patients vs 79 +/- 12% all other patients P = 0.61). Although aortic root replacement carries higher in-hospital mortality in some high-risk subgroups of patients, mid-term survival seems to be less affected by aortic pathology; high-risk patients are expected to have an out-hospital outcome comparable to the low-risk ones.

Two cases of staged replacement of the thoracic aorta using the 'elephant trunk' technique

Two successful cases of staged replacement of multiple aneurysms of the thoracic aorta using the 'elephant trunk' technique are described. The management of both cases is discussed.

Aortic dissection type A surgery: Doppler sonography to evaluate correct carotid artery perfusion during cardiopulmonary bypass

In the surgery of acute aortic type A dissection we have employed preoperative and intraoperative Doppler sonography, to check safe and correct perfusion of the carotid arteries by the cardiopulmonary bypass before instituting cardiac arrest. Ten patients, operated upon for acute aortic type A dissection, were evaluated by means of Doppler sonography and in two patients a very abnormal flow pattern was found in the carotid arteries at the moment of aortic cross-clamping; immediate unclamping allowed temporary antegrade carotid perfusion, while the perfusion technique was readjusted. We report our experience with preoperative and intraoperative Doppler sonography, which appears to be a valuable new method of improving the surgical management of acute aortic type A dissection.

Systemic to pulmonary bronchial blood flow in mitral stenosis

We measured systemic to pulmonary bronchial blood flow [Qbr(s-p)] during total cardiopulmonary bypass in 15 patients with mitral stenosis and elevated pulmonary venous pressure (group A, mean pulmonary wedge pressure = 22.2 +/- 5.4 mm Hg, mean +/- SD) and in 15 patients with coronary artery diseases and normal pulmonary venous pressure (group B). Qbr(s-p) is the volume of blood accumulating in the left side of the heart in the absence of pulmonary and coronary flows. This blood was vented through a cannula introduced into the left atrium and measured. Qbr(s-p) was 76.3 +/- 13.9 ml/min (2.18 +/- 0.37 percent of extracorporeal circulation pump flow) and 22.3 +/- 2.1 (0.63 +/- 0.15) in group A and B, respectively (p less than 0.01). During total cardiopulmonary bypass, pulmonary venous pressure is approximately atmospheric pressure, and no differences in systemic blood pressure, extracorporeal circulation pump flow, and airways pressure were observed between group A and B. Therefore, vascular resistance through the bronchial vessels draining into the pulmonary circulation is reduced in patients with mitral stenosis and elevated pulmonary venous pressure.

Abdominal aortic aneurysm in chronic thoracic dissection. Report of two cases

Two cases of lower abdominal aortic aneurysm in association with chronic thoracic dissections are reported. These infra-renal aortic aneurysms, superimposed on an abdominal extension of the dissection, always require surgical treatment because of their well known tendency to enlarge and rupture. The authors report their experience and discuss the management of this complication in chronic dissections treated surgically.

Extracranial carotid artery aneurysms. Report of two cases

Two cases of extracranial carotid artery aneurysm are reported. Treatment of this uncommon but interesting vascular disorder is still under discussion even if the present tendency is to treat them actively, by reconstructive techniques. We present our surgical experience and discuss the diagnostic problems and management.

Aneurysms of the coronary arteries: one case report

True aneurysms of the coronary arteries are very uncommon. In our institution, from December 1982 to April 1987, in more than 2500 coronarographies, we observed only one case whose angiographic findings revealed a real fusiform aneurysm (at least 3 times the diameter of the original vessel) of the right coronary artery. The same patient exhibited a left anterior descending artery ectasia too, as we already noted in other cases not included in the present report. The other coronary arteries showed no associated lesions. Clinical findings included a previous myocardial inferior infarction and typical precordial effort pain with a basal and stress ECG showing non specific ST-T wave abnormalities. The patient underwent right coronary endoaneurysmectomy with interposition of a saphenous vein graft. Postoperative course was uneventful and 8 months after surgery the patient was asymptomatic, and basal and effort ECG showed no ischemic modification. Control angiogram revealed an optimal anatomical reconstruction with no further evolution of the left anterior descending artery dilatation. The distinction between vessel dilation and an aneurysm is discussed.