[Insertion procedure of the Swan-Ganz catheter].

The Swan-Ganz catheter (the pulmonary artery catheter: PAC) has been used to examine the heart diseases and to evaluate the hemodynamics by the physician in the catheter laboratory and beside the patient's bed. It is also used to monitor the hemodynamics during the cardiac surgery in the operating theater and to manage the patient in the intensive care unit (ICU) postoperatively. A very careful insertion technique is mandatory to avoid various serious complications, such as hematoma formation, arterial centesis, pneumothorax, hemothorax, perforation from cardiac chambers, rupture of the pulmonary artery, and so on. To reduce these complications, standardization of the insertion technique could be useful. When a complication unfortunately occurrs during insertion before surgery, it should be considered to abandon the following operation to avoid catastrophe.

Serum concentration of potassium in chronic heart failure patients administered spironolactone plus furosemide and either enalapril maleate, losartan potassium or candesartan cilexetil.

OBJECTIVE: To retrospectively investigate elevation of serum potassium when spironolactone (25 or 50 mg/day) and furosemide were administered concomitantly with an angiotensin II converting enzyme inhibitor (ACE-I) or angiotensin II receptor blocker (ARB) to patients with chronic heart failure for 12 months and occurrence of hyperkalemia and hypokalemia because of concomitant administration of spironolactone plus an ACE-I or ARB and furosemide. METHODS: Patients with chronic heart failure, who visited departments of cardiovascular internal medicine and cardiovascular surgery at the National Hospital Organization Osaka Medical Center, were enrolled for this study. Serum potassium, blood urea nitrogen (BUN), serum creatinine, uric acid, and serum sodium were determined in every patient at the time of start of treatment and at 3 and 12 months of treatment. Data from patients in Groups A (25 mg/day spironolactone + 40 mg/day furosemide + an ACE-I or ARB) and B (50 mg/day spironolactone + 40 mg/day furosemide + an ACE-I or ARB) were analysed for differences with respect to the ACE-I and ARB used. RESULTS: When 50 mg/day spironolactone plus 5 mg/day enalapril maleate (enalapril) or 50 mg/day losartan potassium (losartan) or 8 mg/day candesartan cilexetil (candesartan) plus 40 mg/day furosemide were concomitantly used, the mean value of serum potassium was significantly elevated only in the group treated with 50 mg/day spironolactone regardless of the concomitant drug. The number of patients with hyperkalemia (>5.5 mEq/L) at 12 months of treatment was 12 (8.8%), while the number of patients with hypokalemia (

A new procedure for chronic atrial fibrillation: bilateral appendage-preserving maze procedure.

BACKGROUND: Atrial transport and atrial natriuretic peptide secretion is severely reduced from normal after the maze III procedure. To improve these factors, we developed a bilateral appendage-preserving maze procedure (BAP-maze). METHODS: Forty-six patients with chronic atrial fibrillation who underwent the BAP-maze procedure were compared with 40 patients who underwent the maze III procedure. The ratio of the peak velocity of the A and E waves of transmitral flow (transthoracic pulsed Doppler echocardiography), the left atrial appendage ejection fraction (transesophageal echocardiography), and the atrial natriuretic peptide secretory reserve during treadmill exercise test were measured at 6 months postoperatively. RESULTS: Sinus rhythm was restored in 44 patients (95.7%) by the BAP-maze procedure and in 39 patients (97.5%) by the maze III procedure. The ratio of the peak velocity of the A and E waves was 0.52 +/- 0.22 in the BAP-maze group and 0.25 +/- 0.19 in the maze III group (p < 0.0001). The left atrial appendage ejection fraction was 44.7% +/- 11.5%, and the atrial natriuretic peptide secretory reserve was greater in the BAP maze group (p = 0.037). CONCLUSIONS: The BAP-maze procedure improved atrial transport and atrial natriuretic peptide secretion as well as simplifying the maze operation, without decreasing its effectiveness against atrial fibrillation.

Renal artery aneurysm causing hydronephrosis.

A 42-year-old man presented with left hydronephrosis incidentally discovered on abdominal echogram during a routine health examination. Color Doppler ultrasonography, intravenous pyelography and angiography revealed a non-calcified renal artery aneurysm of 30 mm in size compressing the pyeroureteral junction and causing hydronephrosis. Three-dimensional computed tomography (3-D CT) using spiral CT clearly displayed the aneurysm located at the first bifurcation of the left renal artery and involving the anterior segmental artery. Decompression was successfully obtained via in situ revascularization of the renal artery after aneurysmectomy. A literature search revealed 12 cases of renal artery aneurysm causing hydronephrosis reported in Japan, although only three cases were documented in other countries, and these reports are reviewed. Use of 3-D CT for evaluation of renal artery aneurysm is advocated.

Early and late outcomes after reoperation for prosthetic valve endocarditis.

OBJECTIVE: Prosthetic valve endocarditis remains a challenging complication after heart valve replacement. To identify predictive risk factors, we have reviewed 30 patients who underwent surgery for prosthetic valve endocarditis between March 1986 and May 1999. METHODS: There were 15 men and 15 women (mean age 51 years). Prosthetic valve endocarditis was classified as early (< or = 1 year after operation) in 10 cases, and as late in the other 20 cases. The most common indication for surgery was moderate to severe congestive heart failure due to prosthetic valve dysfunction in 21 (70%) patients. The average follow-up period was 6.5 years, with a range of 0.3 to 14.1 years. RESULTS: The most common microorganism was Staphylococcus epidermidis in both patients with early (50%) and late prosthetic valve endocarditis (25%). The in-hospital mortality was 13.3% (4/30). There were six late deaths. The actuarial survival at 5 years was 78% and 66% at 10 years. An early onset of prosthetic valve endocarditis was the only significant determinant of both in-hospital mortality (p = 0.005) and overall mortality (p = 0.021). Emergency surgery had a statistically significant relationship with in-hospital mortality (p = 0.045). No significant influence on mortality after reoperation for prosthetic valve endocarditis was found in age, sex, valve position, antecedent native valve endocarditis, or in the type of pathological findings (ring abscess, valve dehiscence, and vegetation). CONCLUSION: Early onset of prosthetic valve endocarditis and emergency surgery were important risk factors for mortality due to prosthetic valve endocarditis.

Mitral insufficiency associated with primary antiphospholipid syndrome and chronic renal failure.

We report a case of 52-year-old woman with primary antiphospholipid syndrome who developed mitral insufficiency and chronic renal failure. Continuous ambulatory peritoneal dialysis was started preoperatively due to thrombocytopenia that was aggravated by hemodialysis. Mitral annuloplasty was performed since the mitral valve was not severely damaged. Her postoperative hemodynamics were stable, and anticoagulant therapy was controlled easily. She recovered from severe thrombocytopenia while on continuous ambulatory peritoneal dialysis. Valvular heart disease is a well known feature of primary antiphospholipid syndrome, and there have been several reports about valve replacement in patients who had antiphospholipid syndrome with or without systemic lupus erythematosus. However, valve repair has been reported in only a few such patients. We believe that valve repair is better than valve replacement in patients with antiphospholipid syndrome because of its hypercoagulable tendency. In addition, it seems that continuous ambulatory peritoneal dialysis is a suitable method for the perioperative management of patients with antiphospholipid syndrome who suffer from chronic renal failure as well as thrombocytopenia, and require cardiac surgery under cardiopulmonary bypass.

Secondary mitral valve replacement in antiphospholipid syndrome and chronic renal failure.

A 48-year-old woman admitted with progressive dyspnea had previously been diagnosed with systemic lupus erythematosus, antiphospholipid syndrome, and chronic renal failure, and had undergone mitral valve replacement with a Carpentier-Edwards pericardial bioprosthesis for mitral insufficiency 9 years before. She suffered a cerebral infarction 5 years earlier, despite appropriate anticoagulant therapy. On admission, echocardiography showed severe bioprosthetic stenosis. Repeat mitral valve replacement was conducted using a Mosaic bioprosthesis. On postoperative day 2, when heparinization was commenced, she suddenly had an epileptic fit. She also developed ischemic necrosis of the fingers and toes, considered secondary to microthrombosis. Aspirin was administered and heparin replaced by warfarin sodium. Necrosis gradually disappeared, and she was discharged 3 months after surgery. The original bioprosthesis showed degenerative changes with significant thrombus formation on cusps, thought to be mainly due to her hypercoagulable state. Considering the thrombophilic tendency in patients with antiphospholipid syndrome, strict management of anticoagulant therapy is required.

Intragastric migration of a pacemaker implanted in the pleural space.

We have encountered a 12-year-old boy with a pacemaker implanted in the left pleural space during early infancy that migrated into the stomach through the diaphragm due to severe scoliosis and occult infection. The intrathoracic implantation of a pacemaker in an infant should be assessed more carefully, taking the volume of the unit into consideration, because of this potentially life-threatening complication.

Aneurysmal pouch on left coronary cusp accompanied by bacterial endocarditis.

A 58-year-old male was admitted to our hospital with a preliminary diagnosis of bacterial endocarditis. After admission, echocardiography indicated the presence of vegetation-like tissues on both the left coronary cusp and the anterior mitral leaflet, although retrograde aortography two months earlier hadn't indicated an abnormal finding on the aortic cusp. The vegetation-like tissues had gradually enlarged despite the administration of antibiotics at another hospital, and aortic and mitral regurgitation had become severe. We decided to perform replacements of the aortic and mitral valves on the day of admission. During the operation, the aortic valve was found not to have vegetation, but an aneurysmal pouch on the left coronary cusp. It was supposed that either bacterial endocarditis or catheter injury had made a part of the aortic cusp weak and intolerant of diastolic pressure gradient, and as a result, the weakened part of the cusp progressively dilated into the left ventricle forming an aneurysmal pouch. To our knowledge, there have been only two previous reports of an aneurysmal pouch on the aortic cusp documented in the literature.

Atrial natriuretic peptide secretion and body fluid balance after bilateral atrial appendectomy by the maze procedure.

OBJECTIVES: One of the earliest recognized postoperative complications of the maze procedure was the fluid retention in the immediate postoperative period. Routine postoperative administration of diuretics markedly reduces the frequency and severity of the fluid retention. However, the cause of the abnormal fluid balance is still uncertain. METHODS: We evaluated 24 patients: 15 patients underwent the maze procedure (maze group) and 9 patients did not (nonmaze group). Blood samples were obtained before and in the time course after operation for atrial natriuretic peptide measurement. To evaluate the influence of atrial natriuretic peptide on the body fluid balance, we also measured the amount of body fluid balance and the total doses of furosemide and dopamine administered after operation. To examine the effect of the maze procedure on atrial natriuretic peptide secretion in chronic phase, we measured plasma atrial natriuretic peptide levels during dynamic exercise in 21 patients who had undergone cardiac operations 2 years before. RESULTS: Plasma atrial natriuretic peptide levels in the nonmaze group significantly increased after operation. In contrast, plasma atrial natriuretic peptide levels in the maze group did not increase, and these levels were significantly lower than in the nonmaze group. Although significantly greater doses of furosemide and dopamine were administered to the maze group than to the nonmaze group, the body fluid balance in the maze group was comparable with that in the nonmaze group in the early postoperative period. The response of atrial natriuretic peptide secretion by exercise was significantly attenuated in the maze group (n = 12) compared with the nonmaze group (n = 9) even 2 years after surgery, although there were no significant differences in heart rate or blood pressure during exercise between two groups. CONCLUSIONS: These results suggest that the maze procedure attenuates atrial natriuretic peptide secretion in the early postoperative period and persists in chronic phase. This attenuated atrial natriuretic peptide secretion may reduce the ability of the kidneys to handle fluid load early after surgery.

The outcome and indications of the Cox maze III procedure for chronic atrial fibrillation with mitral valve disease.

OBJECTIVE: The efficacy of the Cox maze III procedure for chronic atrial fibrillation associated with mitral valve disease is unclear, and so was evaluated in this study. METHODS: In 30 patients, we applied the maze III procedure (cut and suture), except for one modification in the case of a left posterior sinus node artery. After dividing the patients into sinus rhythm and atrial fibrillation groups more than 6 months after the operation, we compared various parameters. RESULTS: Sinus rhythm was restored in 27 patients (90%). One patient had atrioventricular reentrant tachycardia and needed a pacemaker for sick sinus syndrome (3.3%). The f-wave voltage in lead V1, the preoperative cardiothoracic ratio, the preoperative left atrial systolic dimension, and the duration of atrial fibrillation were 0.23 +/- 0.10 mV, 60.4% +/- 5.2%, 57.4 +/- 8.2 mm, respectively, and 5.1 +/- 4.6 years in the group with sinus rhythm, and were 0.06 +/- 0.05 mV, 77.7% +/- 10.3%, 95.3 +/- 24.0 mm, respectively, and 11.8 +/- 5.5 years in the group with atrial fibrillation. These parameters were all significantly different between the groups. Regarding atrial function, a transmitral flow A wave was detected in 66.7% and a transtricuspid flow A wave in 100%. Only the duration of atrial fibrillation had a significant influence on the restoration of left atrial function. CONCLUSION: The maze III procedure was effective for atrial fibrillation associated with mitral valve disease. This procedure should be applied to patients with a cardiothoracic ratio less than 70% and a left atrial systolic dimension less than 80 mm.

A huge coronary aneurysm resulting from a coronary artery-to-left ventricle fistula.

A huge coronary aneurysm resulting from a coronary artery-to-left ventricle fistula is a rare condition. A 57-year-old male had severe recurrent angina attacks. The cause of angina pectoris was a right coronary artery-to-left ventricle fistula with a huge coronary aneurysm. The histological examination of surgically excised specimens revealed that two vertical smooth muscle layers of media of the aneurysm might be associated with dysplasia. Mucoid degeneration was also shown in the intima and around the vasa-vasorum. Abnormal hemodynamics related to the fistula might have induced these vessel wall changes resulting in the huge coronary aneurysm.

Comparative efficacy of the maze procedure for restoration of atrial contraction in patients with and without giant left atrium associated with mitral valve disease.

OBJECTIVES: We sought to determine the effectiveness of the maze procedure for restoring atrial contraction in patients with and without giant left atrium (GLA). BACKGROUND: Although the maze procedure has been reported to be effective for refractory atrial fibrillation, it is unknown whether this procedure can restore effective atrial contraction in patients with GLA. METHODS: Nineteen patients with and 32 patients without GLA were studied with Doppler echocardiography before and after the maze procedure. Peak velocity and the time-velocity integral of the left ventricular diastolic filling wave during atrial contraction (A wave) and the atrial filling fraction calculated as the ratio of the time-velocity integral of the A wave to that of total diastolic filling were compared between patients with and without GLA. A peak A wave velocity > or =10 cm/s was considered to indicate echocardiographic evidence of effective atrial contraction. RESULTS: Regular rhythm with P waves was restored in 10 patients (53%) with and 26 (81%, p < 0.05) without GLA. Four patients (21%) with and 21 patients (66%, p < 0.01) without GLA showed effective atrial contraction by echocardiography. Once atrial contraction was resumed, the degree of atrial contraction was comparable between patients with and without GLA (17+/-5% vs. 17+/-4% for atrial filling fraction at 12 months, respectively). CONCLUSIONS: Although most patients without GLA had restored atrial contraction by the maze procedure, it was resumed in fewer patients with GLA. However, once atrial contraction was resumed, the degree of atrial contraction was comparable between patients with and without GLA. Therefore, the maze procedure may be an option in selected patients with GLA.

Return cycle mapping after entrainment of ventricular tachycardia.

BACKGROUND: The central common pathway, which is the target for ablation in reentrant ventricular tachycardia, can be localized by entrainment mapping techniques. However, localization of the pathway is not always possible because of the elevated pacing threshold and the low voltage and fractionated potentials at the pathway. We examined whether return cycle mapping after entrainment localizes the pathway without pacing at the pathway or recording the potentials from the pathway and determined the required electrode resolution to localize the pathway. METHODS AND RESULTS: Epicardial mapping was performed with 253 unipolar electrodes during and after entrainment of 13 morphologies of ventricular tachycardia that were induced in dogs 4 days after infarction. The return cycle was calculated by subtracting the first activation time from the second activation time after the last stimulus and the return cycle distribution map was constructed for each stimulation site. The return cycle isochrones equal to the ventricular tachycardia cycle length converged on the lines of conduction block irrespective of the stimulation site, and the central common pathway was localized at the region between the intersections of the return cycle isochrones after entrainment from different stimulation sites. The potentials from the central common pathway were not required to localize the pathway, and the mapping accuracy did not change with or without analysis of the potentials from the pathway. According to the correlation between the electrode resolution and the mapping accuracy, an interelectrode distance of 8.5 mm was estimated as sufficient resolution for successful tachycardia termination during radiofrequency ablation guided by return cycle mapping. CONCLUSIONS: Return cycle mapping after entrainment localizes the central common pathway without pacing at the pathway or recording the potentials from the pathway. This new mapping technique could improve the success rate of the ablative procedures.

Electrophysiologic changes in arrhythmogenic substrate following the maze procedure in patients with lone and paroxysmal atrial fibrillation.

Although the Maze procedure is highly successful in restoring sinus rhythm in patients with atrial fibrillation (AF), the electrophysiologic changes that occur after the Maze procedure and its mechanism of action are still unclear. The aims of the present study were to examine the electrophysiologic changes that occur in the arrhythmogenic substrate after the Maze procedure and to evaluate the mechanism by which it prevents lone and paroxysmal AF. The modified Maze procedure was performed in 6 patients (6 men, mean age 47 +/- 7 years) with lone and paroxysmal AF. Electrophysiologic studies were performed before and 35 +/- 8 days after the Maze procedure. Atrial mapping during sinus rhythm revealed that atrial activation propagated smoothly in a concentric circle from the sinus node to other regions in the right atrium and into the coronary sinus before the Maze procedure. Following the Maze procedure, atrial activation propagated selectively through routes produced by incisions or cryoablations in all 6 patients. In addition, double and triple potentials were recorded in regions where conduction blocks were created by the Maze procedure. Neither sinus node function nor AV conduction was changed following the Maze procedure. The Maze procedure did not affect the atrial effective refractory period or the zone of fragmented atrial activity, although the conduction delay zone was increased significantly (p < 0.05). AF was inducible in all 6 patients before the Maze procedure, whereas it was not inducible in any patients after the Maze procedure. The Maze procedure is effective in preventing AF without affecting sinus node function and AV conduction. Intra-atrial conduction block produced by incisions or cryoablations contributes to the prevention of AF.

Huge aneurysm of the sinus of Valsalva following infective endocarditis in Behçet's disease.

A huge aneurysm of the sinus of Valsalva with conduction disturbance as a consequence of infective endocarditis in Behçet's disease is reported. The aneurysm extended not only into the ventricular septum but also to the right atrium and ventricle, with a complicated cavity formation. We speculate that complete atrioventricular block occurred due to an enlargement of the aneurysm into the ventricular septum, leading to a direct conduction system injury. Preoperative echocardiography and aortography were insufficient to recognize the extent of the lesion; subsequent operative examination revealed the true size. At operation, it is important to understand the lesion dimensions fully in order that appropriate surgical procedures be performed.

[Aortic valve replacement with stentless porcine aortic valve].

The Toronto stentless porcine valve (TSPV) is a stentless porcine aortic valve, preserved with glutaraldehyde solution, which has been designed to maintain natural laminar blood flow and improve hemodynamic performance and enhance durability. Aortic valve replacement with TSPV was performed in seven patients. The reason for this indication was advanced age (65 years or more) in six patients and connective tissue disease in another patient. One patient required reoperation because of prosthetic valve endocarditis 4 months after implantation. There were no other valve-related complications. Echocardiographic examination of prosthetic valve function one month after surgery showed no aortic regurgitation in any patient. Transprosthetic gradient was 15.1 +/- 5.0 mmHg. Technical know-how is required for the implantation. The hemodynamic characteristics of the TSPV were excellent. Further follow-up is required to determine durability, but further extensive indication of this valve is expected as a bioprosthesis.

Delayed improvement of autonomic nervous abnormality after the Maze procedure: time and frequency domain analysis of heart rate variability using 24 hour Holter monitoring.

OBJECTIVE: To analyse heart rate variability in patients with atrial fibrillation after the Maze procedure, to investigate whether the procedure damages the cardiac autonomic fibres supplying the sinus node. DESIGN AND PATIENTS: Time and frequency domain analyses of RR variability were performed using 24 hour Holter monitoring one month after surgery in 12 patients with atrial fibrillation who underwent the Maze procedure (Maze group) and in seven patients who underwent cardiac surgery without the Maze procedure (control group). Mean RR intervals (mRR) and the standard deviation of successive RR intervals (SDRR) were determined by time domain analysis, and high frequency (HF), low frequency (LF), and total power (TP) spectral components of RR variability were calculated by frequency domain analysis. Holter monitoring was also performed at six and 12 months after cardiac surgery in the Maze group. RESULTS: Circadian variation (mean (SD)) in mRR (daytime to night time difference: 119 (60) v 302 (143) ms), SDRR (daytime: 8.4 (3.3) v 37.0 (12.0) ms), TP (daytime: 46.7 (16.0) v 171.8 (30.4) ms), HF (daytime: 19.6 (9.9) v 36.7 (7.1) ms2), and LF/HF (daytime: 0.31 (0.07) v 1.18 (0.46)) was decreased in the Maze group at one month compared with the control group (p < 0.01), but showed improvement at six and 12 months (p < 0.05). CONCLUSIONS: Surgery combined with the Maze procedure markedly suppressed the circadian variation of heart rate over a 24 hour period within one month after surgery, mainly because of damage to the innervation of the sinus node. However, at six and 12 months there was restoration of circadian variation, probably as the result of reinnervation of the sinus node.