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1.
AJNR Am J Neuroradiol ; 40(2): 288-294, 2019 02.
Article in English | MEDLINE | ID: mdl-30679216

ABSTRACT

BACKGROUND AND PURPOSE: Incompletely occluded flow diverter treated aneurysms remain at risk of rupture and thromboembolic complications. Our aim was to identify the potential for incomplete occlusion of intracranial aneurysms treated by flow diverters. We investigated whether aneurysm ostium size in relation to parent artery size affects angiographic outcomes of flow diverter-treated sidewall aneurysms. MATERIALS AND METHODS: Flow diverter-treated sidewall aneurysms were divided into "occluded" and "residual" (incomplete occlusion) groups based on 6-month angiographic follow-up. We calculated the ostium ratio, a new parameter defined as the aneurysm ostium surface area versus the circumferential surface area of the parent artery. We also calculated the neck ratio, defined as clinical aneurysm neck diameter versus parent artery diameter from pretreatment 2D DSA, as a 2D surrogate. We compared the performance of these ratios with existing aneurysm morphometrics (size, neck diameter, volume, aspect ratio, size ratio, undulation index, nonsphericity index, ellipticity index, bottleneck factor, aneurysm angle, and parent vessel angle) and flow diverter-related parameters (metal coverage rate and pore density). Statistical tests and receiver operating characteristic analyses were performed to identify significantly different parameters between the 2 groups and test their predictive performances. RESULTS: We included 63 flow diverter-treated aneurysms, 46 occluded and 17 residual. The ostium ratio and neck ratio were significantly higher in the residual group than in the occluded group (P < .001 and P = .02, respectively), whereas all other parameters showed no statistical difference. As discriminating parameters for occlusion, ostium ratio and neck ratio achieved areas under the curve of 0.912 (95% CI, 0.838-0.985) and 0.707 (95% CI, 0.558-0.856), respectively. CONCLUSIONS: High ostium ratios and neck ratios could predict incomplete occlusion of flow diverter-treated sidewall aneurysms. Neck ratio can be easily calculated by interventionists to predict flow-diverter treatment outcomes.


Subject(s)
Intracranial Aneurysm/pathology , Intracranial Aneurysm/therapy , Stents , Treatment Outcome , Aged , Algorithms , Animals , Female , Humans , Male , Middle Aged
2.
AJNR Am J Neuroradiol ; 38(3): 603-610, 2017 Mar.
Article in English | MEDLINE | ID: mdl-28057633

ABSTRACT

BACKGROUND AND PURPOSE: Locally compacting the mesh of a flow diverter by a dynamic push-pull technique can accelerate intracranial aneurysm healing. We asked how this deployment strategy compares with overlapping 2 flow diverters for aneurysmal flow reduction. MATERIALS AND METHODS: Using a high-fidelity virtual stent placement method, we simulated 3 flow-diverter strategies (single noncompacted, 2 overlapped, and single compacted) in 3 aneurysms (fusiform, large saccular, and medium saccular). Computational fluid dynamics analysis provided posttreatment hemodynamic parameters, including time-averaged inflow rate, aneurysm-averaged velocity, wall shear stress, total absolute circulation, and turnover time. We examined the relationship between the achieved degree of compaction and aneurysm orifice area. RESULTS: Flow-diverter compaction resulted in a compaction coverage of 57%, 47%, and 22% over the orifice of the fusiform, large, and medium saccular aneurysm, respectively. Compaction coverage increased linearly with orifice area. In the fusiform aneurysm, the single compacted flow diverter accomplished more aneurysmal flow reduction than the other 2 strategies, as indicated by all 5 hemodynamic parameters. In the 2 saccular aneurysms, the overlapped flow diverters achieved the most flow reduction, followed by the single compacted and the noncompacted flow diverter. CONCLUSIONS: Compacting a single flow diverter can outperform overlapping 2 flow diverters in aneurysmal flow reduction, provided that the compaction produces a mesh denser than 2 overlapped flow diverters and this denser mesh covers a sufficient portion of the aneurysm orifice area, for which we suggest a minimum of 50%. This strategy is most effective for aneurysms with large orifices, especially fusiform aneurysms.


Subject(s)
Blood Vessel Prosthesis , Intracranial Aneurysm/surgery , Algorithms , Blood Vessel Prosthesis Implantation , Cerebrovascular Circulation , Hemodynamics , Humans , Hydrodynamics , Intracranial Aneurysm/diagnostic imaging , Intracranial Aneurysm/physiopathology , Prosthesis Design
3.
J Cardiovasc Surg (Torino) ; 47(6): 705-10, 2006 Dec.
Article in English | MEDLINE | ID: mdl-17043619

ABSTRACT

AIM: The Cox-Maze procedure was introduced nearly two decades ago for the surgical treatment of atrial fibrillation (AF). Recently, our group has replaced most of the incisions of the Cox-Maze procedure with bipolar radiofrequency (RF) ablations (Cox-Maze IV procedure). The purpose of this study was to examine our midterm results with the Cox-Maze procedure using bipolar RF ablation. METHODS: From January 2002 to October 2005, 100 consecutive patients underwent a modified Cox-Maze procedure with bipolar RF ablation for AF; 32 were lone operations, and 68 were concomitant procedures. Follow-up was performed at 1, 3, 6, and 12 months, and then annually thereafter. Heart rhythm was confirmed by electrocardiography. RESULTS: The mean age of patients was 62+/-13 years; 57% were male. Duration of AF was 6.3+/-7.6 years (0.1 to 40 years), 59% had paroxysmal AF, and 34% had permanent AF. Follow-up was complete for all patients with a mean follow-up of 13+/-10 months. At 12-month follow-up, 91% (49/54) of patients were free of AF. Cross-clamp time in the lone Cox-Maze IV procedure patients was 42+/-15 minutes, while it was 101+/-29 minutes for the Cox-Maze IV with a concomitant procedure (compared to 93+/-34 minutes and 122+/-37 minutes for the traditional procedure, P<0.05). There were four operative deaths. CONCLUSIONS: The Cox-Maze IV procedure had good mid-term efficacy. The use of bipolar RF energy significantly decreased operative time and simplified the procedure compared to the traditional Cox-Maze procedure, potentially increasing utilization of the procedure among cardiac surgeons.


Subject(s)
Atrial Fibrillation/surgery , Cardiac Surgical Procedures , Catheter Ablation/instrumentation , Adult , Aged , Aged, 80 and over , Anti-Arrhythmia Agents/therapeutic use , Atrial Fibrillation/drug therapy , Atrial Fibrillation/physiopathology , Cardiac Surgical Procedures/adverse effects , Catheter Ablation/adverse effects , Electrocardiography , Female , Follow-Up Studies , Humans , Male , Middle Aged , Prospective Studies , Recurrence , Research Design , Retrospective Studies , Time Factors , Treatment Outcome
4.
J Cardiovasc Surg (Torino) ; 44(2): 157-61, 2003 Apr.
Article in English | MEDLINE | ID: mdl-12813376

ABSTRACT

AIM: Mitral valve repair for degenerative disease is widely accepted. Because of low risk and excellent late outcomes, surgical intervention is recommended increasingly early when repair appears possible. The place of repair vis a vis continued medical therapy in the elderly, however, is less well defined as there are scant data on their surgical risk. We reviewed our recent results with mitral valvuloplasty for degenerative disease with attention to the influence of age. METHODS: Thirty-day results of mitral valvuloplasty for degenerative disease between January 1996 and April 2000 were examined retrospectively. Patients with ischemic etiology were excluded. Results among those over age 70 years were compared with younger patients. RESULTS: Of 140 patients (78 men and 62 women) aged 27 to 91 (mean 62+/-13) years (44 gs;70 years of age), 61 underwent isolated mitral valvuloplasty, 71 mitral valvuloplasty and coronary artery bypass, and 8 mitral valvuloplasty with other procedures. By multivariate analysis preoperative cardiogenic shock (0.001), but not age, was as a risk factor for death. Among patients stratified by age gs; or <70, there were differences in atrial fibrillation (47.7% vs 29.2%, p=0.03), prolonged ventilation (31.8% vs 15.6%, p=0.03) and hospital stay (median 9.5, range 5-285 vs median 6.5, range 2-36, p=0.001), but not 30-day readmission (15.9% vs 22.9%) or death (5.2% vs 9.1%, p=0.49). CONCLUSION: Operative results for mitral valvuloplasty in the elderly are acceptable. Surgery should not be withheld on the basis of age alone.


Subject(s)
Mitral Valve Insufficiency/surgery , Adult , Aged , Aged, 80 and over , Comorbidity , Coronary Artery Bypass , Coronary Disease/epidemiology , Coronary Disease/surgery , Female , Humans , Male , Middle Aged , Mitral Valve Insufficiency/epidemiology , Mitral Valve Insufficiency/mortality , Multivariate Analysis , Retrospective Studies , Risk Factors
5.
Ann Thorac Surg ; 72(4): 1263-8; discussion 1268-9, 2001 Oct.
Article in English | MEDLINE | ID: mdl-11605613

ABSTRACT

BACKGROUND: This multicenter prospective trial was designed to assess the safety and efficacy of using a robotically-assisted microsurgical system to create endoscopic coronary anastomoses. METHODS: . Thirty-two patients scheduled for elective primary coronary surgery underwent endoscopic anastomosis of the left internal thoracic artery (LITA) to the left anterior descending (LAD) artery. Three thoracic ports (two for instruments and one for a camera) were placed, and a robotic system was used to perform the LITA-LAD graft. Conventional techniques were used to perform the other grafts. Thirty-one patients underwent median sternotomy and 1 patient underwent a limited anterior thoracotomy. RESULTS: . Graft flow was measured in the operating room and averaged 37 +/- 19 mL/min. Mean anastomosis time was 24 +/- 9 minutes. There were three intraoperative revisions (9%). Two were for inadequate flow and one for an inadvertent injury. Each of these grafts was successfully revised by hand. There were no technical failures of the robotic system. Average postoperative length of stay was 5.5 +/- 2.7 days. There were three reoperations for bleeding, but none of these were related to the LAD anastomosis. Two months following the operation, selective angiography revealed a graft patency of 93%. The patients have been followed for 16 +/- 4 months. CONCLUSIONS: This initial prospective multicenter trial documents the feasibility of robotically-assisted coronary bypass grafting. Further trials are warranted to establish the safety and efficacy of this new technology.


Subject(s)
Coronary Artery Bypass/instrumentation , Coronary Disease/surgery , Robotics/instrumentation , Aged , Anastomosis, Surgical/instrumentation , Female , Humans , Male , Microsurgery/instrumentation , Middle Aged , Prospective Studies , Reoperation , Surgical Equipment , Thoracic Arteries/surgery
6.
J Heart Lung Transplant ; 20(10): 1106-14, 2001 Oct.
Article in English | MEDLINE | ID: mdl-11595566

ABSTRACT

BACKGROUND: novel donor heart preservation solution was formulated to produce hyperpolarized arrest with the potassium channel opener, pinacidil. The superior cardioprotective efficacy of this solution has been demonstrated previously when compared to University of Wisconsin solution following 4 hours of hypothermic ischemia. This study tested the hypothesis that pinacidil solution may extend preservation time and provide superior cardioprotective efficacy following 12 hours of ischemia. METHODS: Sixteen rabbit hearts were assigned to receive either pinacidil solution or University of Wisconsin solution in a crystalloid-perfused Langendorff model. Thirty minutes of initial perfusion preceded baseline data acquisition. Left ventricle pressure-volume curves were generated by inflating an intra-ventricular latex balloon. Following cardioplegic administration, hearts underwent 12 hours of hypothermic storage. After 60 minutes of reperfusion, post-ischemic data were acquired. RESULTS: Pinacidil solution demonstrated significantly better myocardial preservation compared to University of Wisconsin solution, with better recovery of developed pressure (53.0 +/- 11.1% vs 20.7 +/- 4.3%, p = 0.017, respectively), post-ischemic coronary flow (55.3 +/- 12.6% vs 23.9 +/- 4.3%, p = 0.034), maximum systolic dP/dT (46.4 +/- 8.3% vs 20.2 +/- 5.1%, p = 0.018) and minimum diastolic -dP/dT (65.3 +/- 10.8% vs 20.2 +/- 5.1%, p = 0.002). Diastolic compliance, expressed as baseline/post-ischemic diastolic slope ratios, was also better preserved by pinacidil solution (0.55 +/- 0.09) vs University of Wisconsin solution (0.40 +/- 0.03) (p = 0.135). CONCLUSIONS: A novel pinacidil solution resulted in improved donor heart preservation during 12 hours of hypothermic ischemia compared to the "gold standard," University of Wisconsin solution. Adopting alternative strategies of hyperpolarized arrest may allow extension of preservation time beyond the limits of traditional depolarizing solutions.


Subject(s)
Heart Transplantation , Organ Preservation Solutions/pharmacology , Organ Preservation/methods , Pinacidil/pharmacology , Vasodilator Agents/pharmacology , Animals , Hemodynamics/drug effects , Myocardial Ischemia/physiopathology , Organ Preservation Solutions/pharmacokinetics , Pinacidil/pharmacokinetics , Rabbits , Time Factors , Vasodilator Agents/pharmacokinetics
7.
Ann Thorac Surg ; 71(4): 1244-9; discussion 1249-50, 2001 Apr.
Article in English | MEDLINE | ID: mdl-11308168

ABSTRACT

BACKGROUND: The extent of proximal and distal aortic resection that should be performed for acute type A aortic dissections remains controversial. METHODS: From 1984 to 1999, 119 patients underwent repair of an acute type A dissection. Distal resection was to the ascending aorta in 78 (66%) and hemiarch in 41 (34%) patients. Proximally, the aortic valve was preserved in 69 (58%) patients, 40 (34%) underwent composite valve grafting, and 10 (8%) underwent separate graft and valve replacement. RESULTS: Operative mortality was higher for separate graft and valve (50%+/-16%) than for valve preservation (16%+/-5%) or composite grafts (20%+/-7%) (p < 0.05). Hemiarch replacement did not increase operative risk compared to distal reconstruction to the ascending aorta (17%+/-6% versus 22%+/-5%, p > 0.71). At 10 years, freedom from reoperation was 81%+/-7% and long-term survival was 60%+/-8%, but neither was related to the proximal or distal surgical technique (p > 0.15). Risk factors for late reoperation included a nonresected primary tear and Marfan syndrome (p < 0.05). CONCLUSIONS: An aggressive surgical approach, including a full root or hemiarch replacement, is not associated with increased operative risk and should be considered when type A dissections extensively involve the valve, sinuses, or arch.


Subject(s)
Aortic Aneurysm, Thoracic/surgery , Aortic Dissection/surgery , Vascular Surgical Procedures/methods , Acute Disease , Adult , Aged , Aged, 80 and over , Aortic Dissection/diagnosis , Aortic Dissection/mortality , Aortic Aneurysm, Thoracic/diagnosis , Aortic Aneurysm, Thoracic/mortality , Female , Follow-Up Studies , Humans , Male , Middle Aged , Predictive Value of Tests , Probability , Reoperation , Retrospective Studies , Risk Assessment , Risk Factors , Survival Rate , Treatment Outcome , Vascular Surgical Procedures/mortality
9.
Ann Thorac Surg ; 72(6): 2003-7, 2001 Dec.
Article in English | MEDLINE | ID: mdl-11789784

ABSTRACT

BACKGROUND: It has been well established that complete revascularization with internal mammary artery (IMA) grafting is important in young patients undergoing coronary artery bypass grafting (CABG). Applying these principles to octogenarians remains controversial. METHODS: From 1986 to 1999, 358 consecutive patients aged 80 to 94 years underwent CABG. Revascularization was complete in 291 (81%) and incomplete in 67 (19%). The IMA was used in 231 (65%) cases. RESULTS: Operative mortality was 7% +/- 1%, but was not statistically different with or without IMA grafting (IMA 5% +/- 2% versus no IMA 10% +/- 3%, p = 0.11) or complete revascularization (p > 0.41). Midterm survival improved with IMA grafting (70% +/- 3% versus 56% +/- 5% at 4 years, p < 0.03; 36% +/- 4% versus 29% +/- 5% at 8 years, p < 0.08), but was not significant beyond 8 years. Among 138 survivors, those with IMA grafts were more likely to be angina free (82% versus 53%, p < 0.001) and in New York Heart Association class I (60% versus 36%, p < 0.03). Survival, recurrent angina, and functional class were independent of completeness of revascularization (p > 0.21). CONCLUSIONS: IMA grafting improved survival, angina, and functional class of octogenarians, but complete revascularization did not have a similar impact.


Subject(s)
Coronary Artery Disease/surgery , Myocardial Infarction/surgery , Myocardial Revascularization/methods , Aged , Aged, 80 and over , Coronary Artery Disease/diagnosis , Coronary Artery Disease/mortality , Disease-Free Survival , Female , Follow-Up Studies , Hospital Mortality , Humans , Male , Myocardial Infarction/diagnosis , Myocardial Infarction/mortality , Postoperative Complications/diagnosis , Postoperative Complications/mortality , Survival Rate , Treatment Outcome
10.
Ann Thorac Surg ; 70(2): 633-8, 2000 Aug.
Article in English | MEDLINE | ID: mdl-10969692

ABSTRACT

BACKGROUND: Cardioplegia has been shown to induce significant cell swelling. This study tested the hypothesis that (1) the [K+][Cl-] product of the cardioplegia solution is the main determinant of myocyte swelling, and (2) reperfusion myocyte shrinkage results from a rectifying Cl- conductance. METHODS: Rabbit ventricular myocytes were superfused with 37 degrees C Krebs-Henseleit solution for 10 minutes. Then cells underwent 20 minutes of superfusion with standard St. Thomas' solution ([K+][Cl-] product = 2566 mmol/L2) and two solutions with lower [K+][Cl-] product (1500 and 700 mmol/L2) at 9 degrees C. Cells were then resuperfused with 37 degrees C Krebs-Henseleit solution for 30 minutes. Cell volume was measured by videomicroscopy. RESULTS: Cells superfused with St. Thomas' having [K+][Cl-] products of 2,566, 1,500, and 700 mmol/L2 swelled by 9.18%+/-3.57%, 5.51%+/-1.08%, and 1.49%+/-1.56%, respectively. Reexposure to Krebs-Henseleit solution caused these cells to shrink by 5.79%+/-1.41%, 8.72% +/-3.68%, and 13.46%+/-5.60%, respectively. This shrinkage was blocked by Cl- channel blockers given at the onset of superfusion. CONCLUSIONS: Lowering the [K+][Cl-] product of St. Thomas' solution attenuated myocyte edema. Myocyte shrinkage during reexposure to Krebs-Henseleit solution resulted from the volume-activated Cl- channel.


Subject(s)
Cardioplegic Solutions/pharmacology , Cell Size/physiology , Heart Arrest, Induced , Myocardium/cytology , Animals , Bicarbonates/chemistry , Bicarbonates/pharmacology , Calcium Chloride/chemistry , Calcium Chloride/pharmacology , Cardioplegic Solutions/chemistry , Cell Size/drug effects , Female , Glucose/chemistry , Glucose/pharmacology , Magnesium/chemistry , Magnesium/pharmacology , Male , Potassium Chloride/analysis , Potassium Chloride/chemistry , Potassium Chloride/pharmacology , Rabbits , Sodium Chloride/chemistry , Sodium Chloride/pharmacology , Tromethamine/chemistry , Tromethamine/pharmacology
11.
J Thorac Cardiovasc Surg ; 120(4): 746-54, 2000 Oct.
Article in English | MEDLINE | ID: mdl-11003758

ABSTRACT

OBJECTIVES: A donor heart preservation solution was designed to use hyperpolarized arrest with the adenosine triphosphate-sensitive potassium-channel opener pinacidil. This solution contained concentrations of potassium, sodium, calcium, magnesium, lactobionate, and the buffer histidine specifically chosen to minimize intracellular calcium accumulation associated with prolonged ischemia. METHODS: Twenty-four rabbit hearts were randomly assigned to receive 1 of 3 preservation solutions in a crystalloid-perfused Langendorff model: (1) prototype solution containing a 0.5 mmol/L concentration of pinacidil, (2) prototype solution without pinacidil as control, and (3) University of Wisconsin solution. Thirty minutes of initial perfusion preceded baseline data acquisition. Data comprised left ventricle pressure-volume curves generated by inflating an intraventricular latex balloon. After cardioplegic administration, hearts underwent 4 hours of hypothermic storage, followed by 60 minutes of reperfusion and postischemic data acquisition. RESULTS: Postischemic developed pressure was better preserved by pinacidil solution (92.4% +/- 4.5%) than by the control (74.9% +/- 3.4%, P =.01) and University of Wisconsin solutions (66.7% +/- 5.1%, P =.001). Diastolic negative dP/dT was better preserved by pinacidil solution (104.4% +/- 10.2%) than by the control (80.2% +/- 4.2%, P =.034) and University of Wisconsin solutions (71.7% +/- 7.0%, P =.015). Diastolic compliance, expressed as baseline/postischemic diastolic slope ratios, was more poorly preserved by University of Wisconsin solution (0.67 +/- 0.07) than by the pinacidil (0.88 +/- 0.05, P =.041) and control solutions (0.87 +/- 0.05, P =.021). Postischemic coronary flow was higher in hearts exposed to pinacidil solution (77.8% +/- 3.0%) than in those exposed to the control (66.8% +/- 2.4%) and University of Wisconsin solutions (70.9% +/- 4.0%, P =.07). CONCLUSIONS: The superiority of the pinacidil solution in this experiment demonstrated that hyperpolarized arrest with potassium-channel openers improves donor heart preservation when administered in a novel histidine-buffered lactobionate-enriched vehicle.


Subject(s)
Cardioplegic Solutions/pharmacology , Heart Transplantation , Organ Preservation Solutions/pharmacology , Organ Preservation , Pinacidil/pharmacology , Vasodilator Agents/pharmacology , Adenosine/pharmacology , Allopurinol/pharmacology , Analysis of Variance , Animals , Glutathione/pharmacology , Insulin/pharmacology , Rabbits , Raffinose/pharmacology , Signal Processing, Computer-Assisted
14.
Ann Thorac Surg ; 69(5): 1363-8, 2000 May.
Article in English | MEDLINE | ID: mdl-10881806

ABSTRACT

BACKGROUND: This study was designed to test the hypothesis that the potassium channel opener pinacidil (Pin) as a pretreatment (PT) agent or additive to St. Thomas' solution (StT) could enhance myocardial protection. METHODS: In a parabiotic rabbit Langendorff model, 36 hearts underwent global normothermic ischemia (1 hour) followed by reperfusion (30 minutes). Cardioplegia (50 mL, every 20 minutes) consisted of: StT; PinPT/StT, where Pin PT preceded StT arrest; Pin alone; Pin in StT (Pin/StT); and Pin in low potassium StT. Systolic function after reperfusion (percent recovery of developed pressure) and compliance (diastolic slope from pressure-volume relationship) were measured. RESULTS: There was no significant difference between StT and PinPT/StT in percent recovery of developed pressure (51.54% +/- 3.5%, 42.17% +/- 4.0%, respectively) or compliance. Likewise, no significant differences occurred between Pin, StT, Pin/StT, and Pin in low potassium StT in percent recovery of developed pressure (58.99% +/- 4.8%, 51.54% +/- 3.5%, 53.09% +/- 3.2%, 66.43% +/- 7.3%, respectively) or compliance. CONCLUSIONS: Pin is as effective a cardioplegic agent as StT; however, its use as a pretreatment or additive to traditional and Pin in low potassium StT provided no additional benefit in functional recovery.


Subject(s)
Cardioplegic Solutions/therapeutic use , Pinacidil/therapeutic use , Potassium Channels/drug effects , Animals , Bicarbonates/therapeutic use , Calcium Chloride/therapeutic use , Coronary Circulation/drug effects , Female , Magnesium/therapeutic use , Male , Parabiosis , Pinacidil/pharmacology , Potassium Chloride/therapeutic use , Rabbits , Reperfusion Injury/prevention & control , Sodium Chloride/therapeutic use
15.
Ann Thorac Surg ; 69(5): 1393-8, 2000 May.
Article in English | MEDLINE | ID: mdl-10881811

ABSTRACT

BACKGROUND: Previous work has shown significant swelling of isolated rabbit myocytes exposed to cold hyperkalemic cardioplegia; however, the effect of warm hyperkalemic cardioplegia on myocyte volume is unknown. This study examined the effect of warm hyperkalemic cardioplegia (St. Thomas' solution) on myocyte volume. METHODS: Myocytes were enzymatically isolated and placed on an inverted video microscope. Tyrode's solution (37 degrees C) was infused for 10 minutes to establish baseline cell volumes. Subsequently, either the control Tyrode's or St. Thomas' was infused either at 37 degrees C and 9 degrees C respectively (n = 5 for all groups) for 20 minutes, followed by a 30-minute reperfusion with 37 degrees C Tyrode's. Cell volume was determined from cell images captured every 5 minutes. RESULTS: Myocyte swelling occurred rapidly on exposure to cold St. Thomas' solution to a maximum of 9.8 +/- 2.1% (p < 0.001). In contrast, myocytes exposed to warm cardioplegia did not show any volume changes during exposure to cardioplegia. However, upon reexposure to Tyrode's, these cells showed shrinkage below their baseline volume (p < 0.001). CONCLUSIONS: The cell swelling associated with hypothermic cardioplegia is prevented by normothermic infusion.


Subject(s)
Cardioplegic Solutions/pharmacology , Heart Arrest, Induced , Myocardium/cytology , Animals , Bicarbonates/pharmacology , Calcium Chloride/pharmacology , Cell Size , Cold Temperature , In Vitro Techniques , Magnesium/pharmacology , Potassium Chloride/pharmacology , Rabbits , Sodium Chloride/pharmacology
16.
Ann Thorac Surg ; 69(6): 1931-2, 2000 Jun.
Article in English | MEDLINE | ID: mdl-10892951

ABSTRACT

We report a case of spontaneous aortic dissection in a young weight lifter without aortic medial disease but with a myofibroblastic proliferation of the aortic adventitia consistent with nodular fasciitis. Successful treatment included ascending aorta replacement with Dacron graft and aortic valve resuspension. We believe that the underlying aortic pathology most likely contributed to the development of the aortic dissection.


Subject(s)
Aortic Aneurysm, Thoracic/surgery , Aortic Diseases/surgery , Aortic Dissection/surgery , Fasciitis/surgery , Weight Lifting/physiology , Adult , Aortic Dissection/pathology , Aorta, Thoracic/pathology , Aorta, Thoracic/surgery , Aortic Aneurysm, Thoracic/pathology , Aortic Diseases/pathology , Aortic Valve/pathology , Aortic Valve/surgery , Blood Vessel Prosthesis Implantation , Fasciitis/pathology , Humans , Male , Risk Factors
17.
J Heart Lung Transplant ; 19(3): 286-97, 2000 Mar.
Article in English | MEDLINE | ID: mdl-10713254

ABSTRACT

BACKGROUND: Hyperpolarized arrest with the potassium channel opener pinacidil has been shown to provide effective myocardial protection during short-term global ischemia. This study tested the hypothesis that pinacidil may provide effective long-term protection for heart transplant preservation. METHODS: Four concentrations of pinacidil (50 microM, 100 microM, 0.5 mM, 1.0 mM) mixed in Krebs-Henseleit solution were compared with University of Wisconsin and St. Thomas' Hospital solutions in a Krebs-Henseleit perfused rabbit Langendorff model (n = 6 for each group). Hearts underwent 4 hours of hypothermic (4 degrees C) storage. Over a wide range of volumes, left ventricular systolic function, diastolic compliance, and coronary flow were measured prior to and following storage. Time to mechanical and electrical arrest, and post-ischemic percent tissue water were also measured. RESULTS: Pinacidil 0.5 mM provided the best preservation of post-ischemic systolic function and coronary flow compared with the other pinacidil concentrations and was statistically equivalent to St. Thomas' solution in terms of post-ischemic systolic, diastolic, and flow properties. However, hearts protected with University of Wisconsin solution had significantly better preservation of systolic function and coronary flow. CONCLUSIONS: This investigation demonstrated that pinacidil in Krebs-Henseleit solution possesses efficacy in long-term donor heart preservation. Pinacidil was equivalent to St. Thomas' solution but inferior to University of Wisconsin solution. Hyperpolarized arrest with potassium channel openers may be a novel strategy to improve donor heart preservation.


Subject(s)
Cold Temperature , Heart Transplantation , Organ Preservation Solutions/pharmacology , Organ Preservation , Pinacidil/pharmacology , Adenosine/pharmacology , Allopurinol/pharmacology , Animals , Bicarbonates/pharmacology , Calcium Chloride/pharmacology , Coronary Circulation , Glutathione/pharmacology , In Vitro Techniques , Insulin/pharmacology , Magnesium/pharmacology , Potassium Channels/metabolism , Potassium Chloride/pharmacology , Rabbits , Raffinose/pharmacology , Sodium Chloride/pharmacology , Ventricular Function, Left
18.
J Card Surg ; 15(4): 256-65, 2000.
Article in English | MEDLINE | ID: mdl-11758061

ABSTRACT

AIM: This prospective study was performed as a Phase 1 Food and Drug Administration clinical trial to assess the safety and feasibility of robotically assisted coronary artery bypass grafting (CABG). METHODS: Eighteen patients undergoing elective CABG were enrolled in this study. Full sternotomy was performed in 17 of 18 patients, while cardiopulmonary bypass and cardioplegic arrest was used in all cases. Robotically assisted CABG of the left internal thoracic artery (LITA) to the left anterior descending artery (LAD) was performed through three ports using a robotically assisted microsurgical system. Conventional techniques were used to perform all other grafts. Blood flow in the LITA graft was measured in the operating room, and when necessary, angiography was performed. Six weeks after the operation, all patients underwent selective coronary angiography of the LITA graft. RESULTS: Robotically assisted coronary artery anastomoses were successfully completed in all patients. Blood flow through the LITA graft was adequate in 16 of 18 patients (89%). The two inadequate grafts were revised successfully by hand. Six weeks after the operation, angiography demonstrated a graft patency of 100% (13 of 13). Mean follow-up has been over 190 days. All patients remain New York Heart Association Angina Class I. CONCLUSION: Robotic assistance represents an enabling technology that may allow the surgeon to perform endoscopic coronary artery anastomoses. Further clinical trials are needed to explore the clinical potential and value of robotically assisted CABG.


Subject(s)
Coronary Artery Bypass/methods , Robotics , Coronary Artery Bypass/instrumentation , Female , Follow-Up Studies , Humans , Male , Microsurgery/instrumentation , Middle Aged , Operating Rooms , Pilot Projects , Prospective Studies , Surgical Equipment , Time Factors , Vascular Patency
19.
J Thorac Cardiovasc Surg ; 119(1): 77-82, 2000 Jan.
Article in English | MEDLINE | ID: mdl-10612764

ABSTRACT

OBJECTIVES: With traditional instruments, endoscopic coronary artery bypass grafting has not been possible. This study was designed to determine the clinical feasibility of using a robotically assisted microsurgical system to create endoscopic coronary anastomoses. METHODS AND RESULTS: Ten patients underwent endoscopic coronary artery bypass grafting of the left internal thoracic artery to the left anterior descending artery. Subxiphoid endoscopic ports (2 for instruments, 1 for a camera) were placed, and a robotic system was used to perform the left internal thoracic artery-left anterior descending artery bypass graft. Conventional techniques were used to perform the other grafts. Blood flow through the left internal thoracic artery graft was measured in the operating room and was adequate in 8 of 10 patients. The 2 inadequate grafts were revised successfully by hand. Six weeks after the operation, selective coronary angiography demonstrated a graft patency of 100% (8/8). There were no technical failures of the robotic system. The only postoperative complication was mediastinal hemorrhage in 1 patient. CONCLUSIONS: This pilot study demonstrates the feasibility of robotically assisted endoscopic coronary artery bypass grafting.


Subject(s)
Anastomosis, Surgical/methods , Coronary Artery Bypass/methods , Endoscopy/methods , Robotics/methods , Anastomosis, Surgical/instrumentation , Coronary Artery Bypass/instrumentation , Coronary Disease/surgery , Feasibility Studies , Female , Humans , Male , Middle Aged , Pilot Projects , Robotics/instrumentation , Thoracic Arteries/transplantation , Treatment Outcome , United States , Vascular Patency
20.
Ann Thorac Surg ; 68(3): 838-43, 1999 Sep.
Article in English | MEDLINE | ID: mdl-10509971

ABSTRACT

BACKGROUND: With traditional instruments, endoscopic coronary artery bypass grafting (ECABG) has not been possible. This study was designed to determine the feasibility of using a robotically-assisted microsurgical system to perform ECABG in a chronic animal model. METHODS: Nine calves were placed on cardiopulmonary bypass after harvesting the left internal mammary artery (LIMA). Subxiphoid endoscopic ports (2 instrument, 1 camera) were placed, and a robotic system was used to perform ECABG between the LIMA and left anterior descending coronary artery. LIMA graft flow (LIMAQ) was measured. Animals were sacrificed at 1 month, and hearts underwent angiographic and histologic analyses. RESULTS: Acute graft patency was 89% (8/9). Two animals died suddenly within the first 48 hours. There was no significant difference in mean acute and chronic (n = 6) LIMAQ (40.9+/-4.7 and 38.5+/-5.0 ml/min, respectively). Survivors had an angiographic patency rate of 100% (6/6), confirmed by histology. CONCLUSIONS: This study shows that ECABG is feasible in a chronic animal model with excellent results.


Subject(s)
Coronary Artery Bypass/methods , Endoscopy/methods , Robotics , Anastomosis, Surgical/methods , Animals , Cattle , Coronary Angiography , Coronary Circulation , Echocardiography , Endoscopes , Feasibility Studies , Microsurgery/instrumentation , Microsurgery/methods , Therapy, Computer-Assisted , Vascular Patency
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