Successful treatment of a patient with severe pulmonary hypertension due to perivalvular leakage at aortic and mitral positions after aortic and mitral valve replacement.

A 33-year-old-man had severe secondary pulmonary hypertension due to perivalvular leakage at the aortic and mitral positions after aortic and mitral valve replacement. Preoperative cardiac catheterization revealed pulmonary artery pressure of 105/45 mmHg and pulmonary vascular resistance of 929 dynes.s.cm(-5) To save the patient, we performed aortic and mitral valve re-replacement, and tricuspid annuloplasty. After surgery, selective pulmonary vasodilators, beraprost sodium, inhaled nitric oxide, and intravenous prostaglandin (PG) I(2) were administered because of persistent severe pulmonary hypertension. Cardiac catheterization on postoperative day 58 showed that the pulmonary artery pressure and pulmonary vascular resistance had decreased to 40/20 mmHg and 87.7 dynes x s x cm(-5), respectively The simultaneous use of inhaled nitric oxide, intravenous PGI(2), and oral beraprost sodium might be useful for treating postoperative persistent pulmonary hypertension.

Pedicled cardiac hemangioma with right ventricular outflow tract obstruction.

A 46-year-old female was admitted to our hospital complaining of dizziness. Echocardiography and magnetic resonance imaging showed a pedicled tumor in the right ventricular outflow tract (RVOT), causing severe obstruction during systole. Resection was performed under cardiopulmonary bypass. Postoperative course was uneventful, with complete disappearance of major symptoms. Histological examination revealed the nature of the tumor to be a benign hemangioma. As reports of cardiac hemangioma causing severe RVOT obstruction are extremely rare, this case warrants attention.

Characteristics of hypertrophic obstructive cardiomyopathy refractory to medical treatment and selection of surgical methods.

BACKGROUND AND AIM OF THE STUDY: Treatment for hypertrophic obstructive cardiomyopathy (HOCM) has been reported; however, there has been no report on the characteristics of medication-responsive and -refractory hypertrophic obstructive cardiomyopathy (HOCM). Using the classification of systolic anterior movement (SAM) which has been previously reported, we tried to identify the characteristics and use them to treat HOCM appropriately. METHODS: The clinical, echocardiographic, catheterization, and surgical data of 29 hospitalized patients with HOCM during 1980 to 1999 were analyzed retrospectively. We classified SAM in all patients by echocardiography. Nineteen patients improved with medical treatment (medical group), and 10 patients underwent surgical treatment because of ineffectiveness of medication (surgical group). We studied the relation between types of SAM and medical/surgical groups, and examined the relation between types of SAM and the surgical methods. RESULTS: Type I SAM was significantly more frequent in the medical group, while type II SAM was more frequent in the surgical group (p = 0.047). Patients in the surgical group underwent mitral valve replacement (MVR), myectomy, or a combination of MVR and myectomy. Left ventricular outflow gradient (LVOG) of over 100 mmHg was recognized in almost all patients with type II SAM. CONCLUSIONS: It was suggested that patients with medication-responsive HOCM tended to have type I SAM and those with refractory HOCM tended to have type II SAM. We consider that in type I SAM, if the position of the papillary muscles changed with medication or myectomy, shift of the chordae and type I SAM were reduced or disappeared. However, in type II SAM, even if the position of the papillary muscles changed, SAM did not disappear because lifting of the mitral leaflets remained. It is therefore suggested that patients with type II SAM should undergo at least MVR.

[Infective endocarditis with a huge mitral vegetation related to atopic dermatitis and high serum level of infection-related antiphospholipid antibody: a case report].

A 24-year-old woman with atopic dermatitis was admitted to our hospital with fever. Echocardiography showed a huge vegetation attached to the posterior mitral commissure without mitral valve dysfunction. Blood culture identified methicillin-sensitive Staphylococcus aureus. The serum level of antiphospholipid antibody was elevated. A splenic infarction occurred on the second hospital day. Surgery to resect the residual mobile vegetation was performed uneventfully on the 6th hospital day. The postoperative course was uneventful, and the patient was discharged after 4 weeks of antibiotic therapy. Preservation of the mitral valve is rare in the face of virulent Staphylococcus infection and the presence of a huge mobile vegetation. These findings were apparently related to the high serum level of infection-related antiphospholipid antibody and atopic dermatitis.

Left ventricular mass index reduction early after an isolated aortic valve replacement with St. Jude Medical 19A-HP.

OBJECTIVES: It has been reported that the left ventricular mass index (LVMI) for the hypertrophic myocardium is reduced at an early stage following surgery. In this study, those factors affecting the changes in early postoperative LVMI were investigated in cases in which a St. Jude Medical 19A-HP (19HP) mechanical heart valve was used. METHODS: We studied 16 consecutive patients with pure aortic stenosis undergoing isolated aortic valve replacement using a 19HP between January 1994 and July 2001. The patients were all female, aged 64 +/- 6 years, with a body surface area of 1.44 +/- 0.10 m2 and preoperative New York Heart Association (NYHA) classification of 2.2 +/- 0.5. All patients underwent transthoracic echocardiography at 4.2 +/- 3.3 days before and 16.3 +/- 10.2 days after operation, and cardiac catheterization within a mean period of one month before operation. The correlations between the decrease of LVMI at 16.3 +/- 10.2 days after operation and perioperative parameters were determined. RESULTS: There was significant LVMI regression postoperatively (15 +/- 12%, p = 0.01), and only a significant negative correlation between the decrease of LVMI and preoperative left ventricular pressure (LVp) [r = -0.74, p < 0.01]. There was no effective LVMI reduction in the high preoperative LVp group (> or = 210 mmHg). CONCLUSION: It is expected that in the high LVp group, huge wall stress was being applied to the left ventricular muscle immediately before surgery and in the early period after surgery. Preoperative LVp is an important index for determining the surgical timing and safe perioperative management. We recommend early surgical treatment before LVp becomes more than 210 mmHg.

In vivo evaluation of a MPC polymer coated continuous flow left ventricular assist system.

The aim of this study was the evaluation of the thrombogenicity and the biocompatibility of the SunMedical EVAHEART left ventricular assist system (LVAS) coated with 2-methacryloyloxyethyl phosphorylcholine (MPC) polymer compared to a diamond-like carbon (DLC) coating. Four calves were implanted with the MPC polymer-coated LVAS. Eight calves were implanted with DLC coated LVAS. The thrombogenicity and biocompatibility of the pumps were evaluated. At explant, 60.0 +/- 37.2% (5-85%) of the pump surface area was still coated with MPC polymer after the duration of 45.0 +/- 32.0 days. In 1 out of 4 MPC and 2 out of 8 DLC coated pumps, there was a very small amount of thrombus around the seal ring; otherwise the blood contacting surfaces were free of thrombus. Major organs were normal except for a few lesions in kidneys from both groups. The MPC polymer coated EVAHEART LVAS seems to have low thrombogenicity and high biocompatibility similar to the DLC coated system. The current study demonstrated that the MPC polymer coating shows great promise for being used as an antithrombogenic substrate for the LVAS due to its ease of application, significant cost benefit, and reduction in anticoagulation therapy in acute postoperative period.

Echocardiographically evaluated site of attachment of atrial myxoma may predict recurrence.

We explore the association between the site of attachment of nonfamilial left atrial myxoma and it's recurrence. Forty-three (11 male and 32 female; mean age, 55.9±13.6 years) of 49 consecutive patients with nonfamilial left atrial myxoma who had been evaluated with preoperative echocardiography, X were available for postoperative follow-up with transthoracic echocardiography, transesophageal echocardiography, or both, for an average period of 85.2±54.2 months (range, 6.5 to 215.5 months). We compared preoperative clinical and echocardiographic features of recurrent and nonrecurrent myxomas. Three (7%) of the 43 cases of atrial myxoma recurred at the same site after 24.1±7.6 months. Involvement of the mitral valve annulus or mitral valve leaflet (3 vs 0,p<0.001) was observed in the recurrent myxomas, but the two groups did not differ significantly in any other clinical features, laboratory data, or echocardiographic features of the recurrent and nonrecurrent myxoma. Preoperative echocardiographic observation of involvement of the mitral valve annulus or mitral valve leaflet may predict recurrence after surgery. Regular follow-up echocardiography was useful in the early detection of recurrence.

A comparison of the in vivo performance of the 19-mm St. Jude Medical Hemodynamic Plus and 21-mm standard valve.

BACKGROUND: In the present study we analyzed the in vivo performance of the 19-mm St. Jude Medical Hemodynamic Plus aortic prosthesis (19HP), evaluated the midterm performance of 19HP in the aortic position, and compared the implantability and hemodynamic characteristics of this valve with those of the 21-mm standard St. Jude Medical valve (21SD) in adult patients with aortic stenosis and a narrowed aortic annulus. METHODS: From February 1994 to December 1999, 60 patients who underwent isolated aortic valve replacement with either the 19HP (n = 31) or the 21SD (n = 29) were studied. Comparison between the two models included analysis of early and late mortality and morbidity. Pre- and postoperative echocardiography was performed in all patients to evaluate and compare the hemodynamic performance of both prosthetic valves. The postoperative serum lactic dehydrogenase activity was measured in both groups of patients as an indicator of hemolysis. RESULTS: The mean body surface area was 1.46 +/- 0.16 m2 in the 19HP group and 1.49 +/- 0.13 m2 in the 21SD group (p = 0.1577). Other than female dominance in the 19HP group, there was no statistically significant difference between the two groups in terms of preoperative variables (age, preoperative pressure gradients, and New York Heart Association functional class). The average postoperative peak pressure gradient was 23.3 +/- 10.5 mm Hg in the 19HP group and 27.9 +/- 9.9 mm Hg in the 21SD group (p = 0.0666). There was no hospital death in either group. Six-year follow-up was completed in both groups of patients. Late death occurred in 1 patient in the 19HP group (1.09% per patient-year). Actuarial survival at 6 years was 92.3% +/- 7.4% in the 19HP group, and 100% in the 21SD group (p = 0.33). The linearized complication rate was 1.09% per patient-year and 1.02% per patient-year for thromboembolism, and 1.09% per patient-year and 1.02% per patient-year for anticoagulant-related hemorrhage in the 19HP group and the 21SD group, respectively. Freedom from all complications at 6 years did not show any significant difference between the two groups (p = 0.54). Although left ventricular mass indices decreased significantly after aortic valve replacement in both groups (19HP group, p = 0.0002; 21SD group, p = 0.0006), there were no significant differences in the two indices between the groups after aortic valve replacement (p = 0.999). There was no significant difference in the lactic dehydrogenase level between the two groups (p = 0.4915). CONCLUSIONS: In vivo hemodynamic performance of the 19HP valve as well as the early and intermediate clinical outcome up to 6 years was satisfactory and corresponded closely to that of the 21SD valve in adult patients. The 19-mm Hemodynamic Plus model can be recommended in patients with a measured 19-mm annulus and this valve will minimize the need for the aortic annular enlargement procedure.

Extracorporeal membrane oxygenation and left ventricular assist device: a case of double mechanical bridge.

A 14-year-old boy with dilated cardiomyopathy with cardiac arrest was successfully implanted with a left ventricular assist device (LVAD) after 6-day extracorporeal membrane oxygenation (ECMO). He had multiple organ failure at the initiation of ECMO, but the failed organs recovered during assisted circulation, leading to LVAD implantation. This case showed the advantages of the "double bridge" such as: (1) quick and easy installation for acute cardiogenic shock, (2) providing intervention time for complications refractory to LVAD implantation, and (3) providing evaluation time for potential LVAD implantation and transplant candidates.

Acute aortic dissection in a patient with idiopathic dilated cardiomyopathy.

Surgical treatment of acute aortic dissection in a patient with idiopathic dilated cardiomyopathy is rare. A 57-year-old man diagnosed with idiopathic dilated cardiomyopathy with left ventricular dimension of 59 mm in diastole, left ventricular dimension of 47 mm in systole, and fractional shortening of 0.19 on echocardiography developed type A acute aortic dissection. Emergency surgery was conducted for ascending aorta and hemiarch repair for ascending aorta redissection and dilation. The postoperative course was uneventful under appropriate hemodynamic control. Standardized criteria for aortic dissection in a patient with poor left ventricular contraction have not established, but surgery should be considered for all patients in good preoperative condition when it is the only effective life-saving alternative.

Acute occlusion of coronary artery bypass graft with nonionic contrast medium.

The use of nonionic contrast media should be beneficial in patients with cardiac disease because such media are less chemotoxic. Using iopamidol under heparinization, we treated 4 cases of acute thromboembolic occurrence including occlusion of coronary artery bypass grafts and associated native coronary arteries. While the majority of patients do not experience this complication, care must be taken to avoid major adverse effects.

Effects of milrinone for right ventricular failure after left ventricular assist device implantation.

Right ventricular failure after left ventricular assist device implantation sometimes requires additional mechanical right ventricular support. The effectiveness of nitrates, prostaglandin, or nitric oxide inhalation in such cases has already been reported. However, there are few reports on the administration of phosphodiesterase inhibitor for right ventricular failure after left ventricular assist device implantation. We report two patients with right ventricular failure after left ventricular assist device implantation successfully treated with milrinone. Both had residual pulmonary hypertension due to high pulmonary vascular resistance after left ventricular assist device implantation. However, intravenous milrinone caused a significant reduction in pulmonary vascular resistance and an increase in left ventricular assist device flow. Milrinone acts as both an inotropic agent and a direct vasodilator, and thus may avoid the need for mechanical support for right ventricular failure due to residual pulmonary hypertension after left ventricular assist device implantation.

Arch-first technique for aortic arch operation using branched graft.

To compare the arch-first technique with conventional aortic arch reconstruction 19 patients were randomly assigned to either procedure. Nine patients underwent the arch-first technique (group A) and 10 underwent the conventional technique (group B). There were no hospital deaths and no significant differences between groups in terms of intraoperative bleeding or the duration of operation cardiopulmonary bypass aortic crossclamping recovery from anesthesia or intensive care. The mean duration of retrograde cerebral perfusion via the superior vena cava was significantly shorter in group A (41.7 +/- 10.4 min) than group B (63.9 +/- 10 min). Transient neurologic dysfunction was noted in 4 (44%) patients in group A 6 (60%) in group B postoperatively but there was no permanent neurologic dysfunction in either group. The arch-first technique makes it possible to reduce the duration of cerebral ischemia retrograde cerebral perfusion via the superior vena cava reestablish antegrade cerebral perfusion earlier without damaging severely atheromatous arch vessels or conducting retrograde cerebral perfusion via a femoral artery. This technique has the potential to reduce the incidence of neurologic dysfunction.

Biventricular Bypass with Oxygenation for Postcardiotomy Ventricular Failure.

Between January 1984 and March 1995, biventricular bypass (BVB) with oxygenation was used in 17 patients for postcardiotomy ventricular failure at the Heart Institute of Japan, Tokyo Women's Medical College. Of the 17 patients, 12 (70.6%) were weaned from the circulatory support, and 8 (47.1%) were discharged from the hospital. The time interval from the end of cardiopulmonary bypass to the start of BVB was significantly shorter in weaned patients than in unweaned patients. The duration on support also has been shortened significantly in the last 6 years, compared with the earlier 6 years. Causes of death were severe heart failure or ventricular arrhythmia in 6 patients and multiple organ failure in 3 patients. These results suggest that early application and timely weaning from biventricular bypass with oxygenation might be the effective circulatory support of choice for treatment of postcardiotomy ventricular failure.

Clinical Application of a Newly Developed Autoflow Control System for the Terumo Centrifugal Pump: From External Control to Built-in Direct Control.

We have developed an autoflow control system for the Terumo Capiox centrifugal pump, the SP-101. First, we made an external control system regulated by a personal computer through a serial communications line. Although an in vivo experiment using a goat showed excellent performance in regulating the flow, a communication error that caused an abrupt and instantaneous flow fluctuation was noted occasionally. Therefore, we incorporated a check-sum function to solve this problem. After this improvement, 5 patients safely underwent cardiopulmonary bypass using a pump having this autoflow control. As the next step for more practical usage, we developed a built-in autoflow control system in which the control device is entirely incorporated into the console without a communications line. This system demonstrated better response and reliability than the external control system and was applied successfully in 3 patients. In conclusion, this autoflow mode will expand the usage of centrifugal pumps through improved handling.

A New Supportive Method for Aortic Aneurysm Surgery: Centrifugal Left Heart Bypass Combined with an Oxygenator and a Heat Exchanger.

A new supportive method of centrifugal left heart bypass with oxygenation was performed in 25 patients and compared with standard left heart bypass in 45 patients. Femoro-femoral bypass was selected in another 6 patients because of the presence of a left atrial adhesion. Intraoperative complications related to standard left heart bypass, hypoxia, hypothermia, and ventricular fibrillation, were eliminated by using this method. This supportive method maintained good hemodynamics and improved the surgical result of extended thoracoabdominal aortic replacement. Hospital deaths decreased from 6.7% to 3.2%.

Basic Performance of a Miniature Intraventricular Axial Pump.

A miniature intraventricular axial pump for left ventricular (LV) support is under development. This pump was designed for placement in the LV cavity by insertion through the LV apex with the outlet located at the ascending aorta via the aortic valve. The basic hydro-dynamic characteristics represented as a relationship between pump head (H) and flow (Q) showed a negative linear relationship under a constant head. This characteristic was generally the same as that obtained by other axial rotation pumps. However, the actual H-Q relationship was represented as anticlockwise "loops" caused by the contraction of the natural LV. The comparative in vitro data on these H-Q loops showed that the shape of the loops was changed drastically by the connecting condition between the pump and natural cardiovascular system.

Less Blood Damage in the Impeller Centrifugal Pump: A Comparative Study with the Roller Pump in Open Heart Surgery.

A centrifugal pump with an impeller (Nikkiso Centrifugal Pump, Model HPM15; Nikkiso Co. Ltd.) was applied to cardiopulmonary bypass (CPB) in 14 patients who underwent elective coronary artery bypass grafting. Serum hemoglobin level, platelet count, and serum p-thromboglobulin (pTG) level were measured during CPB. The results were compared with those obtained in a comparative roller pump (RP) group (n = 10). There was no difference in the time on CPB between the NP (109 min) and RP (121 min) groups. The serum pTG level (ng/ ml) was lower in the NP group than in the RP group (obtained 90 min after the initiation of CPB). The plasma-free hemoglobin level also was lower in the NP group than in the RP group (obtained 90 min after the initiation of CPB, 120 min after the initiation of CPB, immediately after the termination of CPB, 3 h after termination of CPB; p < 0.01). There was no significant difference in platelet depletion. The HPM15 pump showed excellent hemodynamic performance with less blood trauma compared with the roller pump in its clinical application to open heart surgery.

High-Resolution Fluorescent Particle-Tracking Flow Visualization within an Intraventricular Axial Flow Left Ventricular Assist Device.

Flow visualization is typically applied in blood pump development to both confirm the design expectations and identify regions that may be predisposed to blood element deposition and trauma. Rotary pumps, in particular, place high demands on the technique chosen to visualize the flow given the limited visual accessibility of the flow path and the high impeller speeds. Fluorescent image-tracking velocimetry currently is used at the University of Pittsburgh Medical Center to visualize flow accurately inside of these pumps both qualitatively and quantitatively. Flow patterns under steady conditions within an intraventricular axial flow, left ventricular assist pump (prototype No. 7, SUN Medical Technology Research Corporation, Nagano, Japan) were investigated using this technique. The flow fields at the impeller-stator interface and at the pump outlet were given specific attention. This allowed the assessment of the fluid dynamics throughout the hydrodynamic design limits of the pump.