Socio-economic effects and cost saving potential of remote patient monitoring (SAVE-HM trial).

OBJECTIVE: In the SAVE-trial we evaluated the safety, reliability and improvements of patient management using the BIOTRONIK Home Monitoring®-System (HM) in pacemaker (PM) and implanted cardioverter defibrillator (ICD) patients. DESIGN: 115 PM (Module A) and 36 ICD-patients (Module B) were recruited 3 months after implantation. PATIENTS: 65 patients in Module A were randomised to HM-OFF and had one scheduled outpatient clinic follow-up(FU) per year, whereas patients randomised to HM-ON were equipped with the mobile transmitter and discharged without any further scheduled in-office FU. In Module B 18 patients were randomised to HM-OFF and followed by standard outpatient clinic controls every 6 months; 18 patients were randomised to HM-ON receiving remote monitoring plus one outpatient clinic visit per year; unscheduled follow-ups were performed when necessary. RESULTS: The average follow-up period was 17.1 ± 9.2 months in Module A and 26.3 ± 8.6 months in Module B. In both modules, the number of FUs per year was significantly reduced (Module A HM-ON 0.29 ± 0.6 FUs/year vs HM-OFF 0.53 ± 0.5 FUs/year; p b 0.001; Module B HM-ON 0.87 ± 0.25 vs HM-OFF 1.73 ± 0.53 FU/year,p b 0.001). Cost analysis was significantly lower in the HM-ON group compared to the HM-OFF group (18.0 ± 41.3 and 22.4 ± 26.9 € respectively; p b 0.003). 93% of the unscheduled visits in Module B were clinically indicated,whereas 55% of the routine FUs were classified as clinically unnecessary. CONCLUSION: Remote home monitoring of pacemaker and ICD devices was safe, reduced overall hospital visits, and detected events that mandated unscheduled visits.

[Perioperative management of patients with implanted pacemakers or cardioverter/defibrillators. Recommendations of the Austrian Society for Anaesthesiology, Resuscitation and Intensive Care Medicine, the Austrian Society for Cardiology and the Austrian Society for Surgery]. / Perioperatives Management von Patienten mit implantiertem Schrittmacher oder Kardioverter/Defibrillator. Empfehlungen der Osterreichischen Gesellschaft für Anästhesiologie, Reanimation und Intensivmedizin, der Osterreichischen Kardiologischen Gesellschaft und der Osterreichischen Gesellschaft für Chirurgie.

The perioperative risk for patients with pacemakers or implanted cardioverter/defibrillators (ICD) is mainly dependent on the underlying disease. However, severe to life-threatening complications of the implanted system can occur due to electromagnetic interference in the environment of the operation. These complications can be prevented or adequately treated by taking special precautions and measures. Even though the currently available data on the optimal perioperative management to pacemakers and ICDs is still unsatisfactory, the increasing clinical relevance of this topic was the reason for the formulation of recommendations by an interdisciplinary working group in Austria.

Psychometric properties of an established heart disease specific health-related quality of life questionnaire for pacemaker patients.

Little is known about the HRQL of pacemaker patients due to the limited availability of disease-specific instruments. The aim of the Pacemaker Patients Quality of Life (PAPQoL) study was to determine the psychometric properties for the MacNew Heart Disease Health-related Quality of Life Questionnaire (MacNew) in patients before and after pacemaker implantation. Patients with a given indication for pacemaker therapy (N = 68) completed two self-administered HRQL instruments, the SF-36, a well-known and psychometrically sound health survey, and the MacNew, a reliable and valid heart-disease-specific HRQL instrument, before and one, three and six months after pacemaker implantation. We assessed disease severity with the New York Heart Association (NYHA) classification. Test-retest reliability, intra-class correlation, Cronbach's alpha, validity coefficients, sensitivity analyses (effect sizes) and confirmatory factor analysis were carried out. The MacNew demonstrated adequate reliability (Cronbach's alpha and ICCs > 0.80 on all scales), validity (correlations between similar SF-36 and MacNew subscales > 0.80), and responsiveness (all effect sizes > or = 0.67) in pacemaker patients. The MacNew demonstrates adequate psychometric properties for evaluating HRQL in patients before and after pacemaker implantation.

Cardiac myxomas: 24 years of experience in 49 patients.

OBJECTIVES: In this single-center study we reviewed our experience with a significant number of cardiac myxoma cases occurring over the past two decades. PATIENTS AND METHODS: Cardiac myxomas represented 86% of all surgically treated cardiac tumors at our center. Specifically, there were 49 consecutive patients, each with at least one myxoma. A detailed clinical, immunological, and echocardiographic long-term examination of 37 patients revealed one recurrent myxoma. RESULTS: Most myxomas originated from the left atrium (87.7%), but also much less frequently from the mitral valve (6.1%), from the right atrium (4.1%), and from the left and right atria (2.0%). The myxomas produced a prolapse into the left ventricle in 40.8% of the patients, mitral stenosis in 10.2%, and threatened left ventricular outflow tract obstruction in 2.0%. Multiple myxomas were found in 20.4% of the patients. Cardiac signs appeared in 93.9% of the patients. Preoperative embolic events had occurred in 26.5%. Immunologic alterations were present in 87.5%. For resection, a bilateral atriotomy was used. An additional aortotomy was needed to expose one mitral valve myxoma. Postoperatively, 81.1% of the patients remained without cardiac symptoms. The early mortality rate was 2.0% and the late mortality rate was 6.1%. Long-term prognosis was excellent with an actuarial survival rate of 0.74. Specific immunologic alterations were found in 71.4% of the patients. The actuarial freedom from reoperation of the myxoma was 0.96. The rate of reoperations was low with 2.0% after 24 years. CONCLUSIONS: Myxomas were usually detected and operated on in symptomatic patients. A high index of suspicion seems important for early diagnosis. Immunologic findings may play an additional role in confirming the diagnosis and the recurrence of a myxoma. Immediate surgical treatment was indicated because of the high risk of embolization or of sudden cardiac death. Also, a familial genesis must be excluded in myxoma patients.

Left ventricular architecture after valve replacement due to critical aortic stenosis: an approach to dis-/qualify the myth of valve prosthesis-patient mismatch?

OBJECTIVES: Left ventricular hypertrophy in patients with critical aortic stenosis (AS) is an adaptive process that compensates for high intracavitary pressure and reduces systolic wall stress followed by an increase in myocardial masses. In the present prospective clinical trial, we investigated long-term compensatory changes in left ventricular geometry and function after aortic valve replacement using mechanical bileaflet prostheses with the main emphasis on the small-sized aortic annulus and valve prosthesis-patient mismatch. METHODS: A total of 58 patients with critical AS were assigned to the following groups according to the predictive value of prosthetic valve area index (VAI): group EXMIS: 29 patients (VAI < or =0.99), expected mismatch; group NOMIS: 29 patients (VAI < or =0.99), no mismatch. At controls T(0) (before operation/operation (OP), T(1) and T(2) (4 and 20 months after OP) the left ventricular geometry was recorded by means of Imatron electron beam tomography and the transprosthetic velocities were measured by echocardiography. RESULTS: Statistical analysis showed a consistent reduction in the absolute (P=0.04) and indexed (P=0.04) left ventricular myocardial mass for both cohorts; furthermore, there was a significant difference between EXMIS and NOMIS patients concerning the factors, time and mass reduction (P=0.005), because of distinct baselines. A logistic regression report revealed preoperative cardiac output, absolute left ventricular myocardial mass, perfusion, body surface area and the native valve orifice area as predicting coefficients and factors for a minimum mass reduction of 25%. We explain a mathematical formula that turned out to be the most sensitive for correctly classified factors. CONCLUSIONS: The left ventricular geometry and transprosthetic velocities resulted in the same postoperative recovery for both EXMIS and NOMIS patients. The presented data showed that valve prosthesis-patient mismatch had no influence in several stepwise logistic regression models. We conclude that modern mechanical bileaflet prostheses allow both acceptable hemodynamics and recovery of left ventricular hypertrophy, even in small aortic annuli.

[Forensic aspects of a trainee in robotic surgery of the heart]. / Forensische Aspekte eines Anfängers in der Roboterchirurgie am Herzen.

The grounds for liability with robotic surgery include damage to patients, causality, illegality and guilt. The patient must receive very comprehensive information on the treatment under consideration, his/her risk and what will be done in the case of technical failure. The surgeon operating the robotic device is obliged to provide normal conscientious care and state-of-the-art treatment. In addition, there is possible neglect of supervisory duties vis-à-vis other hospital personnel to be considered. A special problem is posed by a forensic physician who lacks experience in robotic surgery. There should be a surgeon at the operating table who is at least equally skilled as the surgeon operating the monitor. Robotic surgery must ultimately be at least as effective as conventional surgery, if not better. It must, however, be borne in mind that in cases involving this new technology, it is that patient who is the pioneer.

[Autocapture(TM) and Capture Management(TM) Current concepts in pacing threshold and output management]. / Autocapture(TM)- und Capture-Management(TM) Aktuelle Konzepte zur automatischen Reizschwellenmessung und Anpassung der Stimulationsamplitude.

Pacing threshold is not a stable value during the pacemaker's life. It is affected by many physiological, pharmacological and pathophysiological factors. A pacing system able to confirm capture and automatically adjust its output to the actual pacing threshold is highly desirable for a prolonged battery life and maximal patient safety. The Autocapture(TM) of St. Jude Medical and the Capture Management(TM) of Medtronic are currently available on the market. The key feature is the measurement of the evoked response (ER) signal by the pacemaker for capture confirmation. In case of loss of capture, the Autocapture(TM) System delivers a back up safety pulse of 4.5 Volt and 0.49 ms and starts a new threshold search. The pacemaker adapts its output to 0.3V/0.25V above the newly measured threshold. This system needs bipolar leads with low polarization for the first generation in Microny® and Regency® pacemakers; in the second generation with Affinity® and Integrity® pacemakers various bipolar leads are suitable. The Capture Management(TM) System of Medtronic, available in the Kappa® DR 700 series, performs a two point automatic threshold search once every day during rest. The output is determined by the programmed safety margin (nominal 1.5×voltage threshold). A backup pulse is only delivered during the threshold search. No special electrodes are necessary. These functions were shown to work safely and efficaciously in multicenter trials to decrease the current consumption with a prolongation of battery life up to 142%. The patients safety was increased by identifying changes of the capture threshold over time and adjusting the pacing stimulus. The conventional safety margins of 100% might not be safe for all patients. We also learned much about lead maturation and lead instability by the possibility of continuous follow-up of threshold changes in a larger group of leads in order to identify the risk group of about 10% of patients with late threshold increase and lead instability.

Left ventricular outflow tract obstruction due to valve myxoma.

A life-threatening left ventricular outflow tract obstruction developed in a 26-year-old man because of a very uncommon myxoma emerging from the ventricular side of the mitral valve. Immediate surgical treatment was indicated because of high-risk factors reported herein. After transaortic resection of a single myxoma, the progress of this patient has been excellent, especially as a familial myxoma could be excluded.

[Lead stability in long-term follow-up of bipolar leads]. / Sondenstabilität im Langzeitverlauf bipolarer Sonden.

From 1990 to 1999, 2,853 ventricular and 1,084 atrial bipolar leads of various manufacturers (Medtronic, Biotronik, Vitatron, Ela, Pacesetter and Stöckert) were implanted during first implantations of pacemakers at the University of Graz, Dept. of Cardiac Surgery. Surgical complications with the need of reintervention were analyzed during a follow up period of up to 10 years. The overall lead-related complication rate for ventricular bipolar leads was 6.5% (187 of 2,853) and 5.3% (58 of 1,084) for atrial bipolar leads. Early complications within the first month were higher in the atrium (5.3% versus 2.2% in the ventricle), primarily due to dislocation, late complications were higher in the ventricle (4.3% versus 2% in the atrium) due to insulation problems and lead fracture. Insulation material had a marked influence with a higher failure rate in some leads with polyurethane insulation compared with silicone. Therefore we recommend a close follow-up of bipolar polyurethane leads by measurement of chronic impedance in order to assess insulation problems as early as possible.

Minimally invasive versus conventional aortic valve operations: a prospective study in 120 patients.

BACKGROUND: Risk evaluation comparing the minimally invasive and standard aortic valve operations has not been studied. METHODS: Four surgeons were randomly assigned to perform the minimally invasive (L-shaped sternotomy) (group 1) or the conventional (group 2) operation in 120 patients exclusively. RESULTS: In both groups (n = 60) a CarboMedics prothesis was implanted in 90% of patients. There was no significant difference in the cross-clamping period (group 1, 60 minutes; range, 35 to 116 minutes), in the duration of extracorporal circulation (group 1, 84 minutes; range, 51 to 179 minutes) or in the time from skin-to-skin (group 1, 195 minutes; range, 145 to 466 minutes). Patients in group 1 were extubated earlier (p<0.001), the postoperative blood loss was less (p<0.001), and the need for analgesics was reduced (p<0.05). In 5 patients in group 1 a redo operation was required for bleeding (p>0.05), 3 patients in group 1 required a redo operation because of paravalvular leakage or endocarditis (p>0.05), the 30-day mortality rate was 1.6%. Overall the survival rate was 95% in group 1 and 97% in group 2 (mean follow-up, 294 days; range, 30 to 745 days). CONCLUSION: The advantages of minimally invasive aortic valve operation include reduced trauma from incision and duration of ventilation, decreased blood loss and postoperative pain, the avoidance of groin cannulation, and a cosmetically attractive result. Simple equipment is used with a high degree of effectiveness and with no sacrifice of safety. Our study demonstrated the practicability and reliability of this new method.

Invasive ductal carcinoma of the male breast expanding from pacemaker pocket decubitus.

After twenty-five years of therapy with different unifocal pacemaking systems, an 84-year old male patient developed a nonseptic pacemaker decubitus. A rare incidental finding of invasive ductal carcinoma of the right mammary gland was surgically treated by a generous excision of the tumor and by consecutive modified radical mastectomy. According to published literature, the association of invasive ductal carcinoma arising from a pacemaker pocket decubitus and followed by curative treatment has not been previously reported. We do conclude that pacemaker generators in close relationship to the mammary gland should be considered with suspicion.

A high-resolution esophageal electrocardiogram for monitoring atrial activity in the hypothermic potassium-arrested heart.

Atrial electrical activities during hypothermic, K(+)-induced cardioplegic arrest correlate with an increased incidence of postoperative supraventricular dysrhythmias in coronary artery bypass graft patients. Surface electrocardiogram (ECG) (S-ECG) may be insufficiently sensitive to detect such activity intraoperatively, and invasive methods are impractical and traumatic. From induction of anesthesia until the end of surgery, esophageal ECG signals were detected with a new bipolar esophageal probe and a new high-resolution preamplifier (frequency range 0.01-2000 Hz). The S-ECG and the esophageal ECG (E-ECG) were evaluated independently in 18 patients. Eight of 18 patients presented during cardioplegic arrest a mean of 483 +/- 119 high-amplitude, biphasic P components (mean amplitude 0.7 +/- 0.1 mV, range 0.35-1.15 mV) per patient (mean 36 +/- 6 [5-59] potentials/min) similar to those coinciding with the surface ECG P-waves during sinus rhythm. Six of these eight patients presented a mean of 29 +/- 11 low atrial activities (mean amplitude 0.14 +/- 0.023 mV; range 0.1-0.25 mV) per patient (mean 8.4 +/- 5.6 [2.3-48] potentials/min) in the E-ECG. In the S-ECG, one patient of these eight presented 26 P waves during cardioplegic arrest simultaneously with activities in the E-ECG. During the first 5 days, seven of eight (88%) patients with atrial activities in the E-ECG versus 3 of 10 (30%) patients without atrial activities developed supraventricular tachyarrhythmias postoperatively (P < 0.05). This new high-resolution E-ECG device detected in a beat-to-beat technique more atrial activity during cardioplegic arrest than a S-ECG and offered the advantages of artifact exclusion and better prediction of postoperative supraventricular dysrhythmias.

Concomitant procedures in the small versus standard aortic root.

BACKGROUND AND AIMS OF THE STUDY: Aortic valve replacement (AVR) in the small aortic root (SAR) has always been a severe challenge with an uncertain surgical outcome. The purpose of this study was to assess the surgical and clinical performance of 19 mm and 21 mm CarboMedics valves (CPHV) based on a review of valve-related morbidity and mortality over a period of six years. METHODS: A total of 361 patients undergoing aortic valve replacement (AVR) with the CPHV between January 1989 and August 1995 was subdivided and studied. (i) Group A patients (n = 137) received 19 mm or 21 mm prostheses; subgroup AI (n = 85) underwent isolated AVR and subgroup AII (n = 52) underwent AVR with associated cardiac procedures. (ii) Group B patients (n = 224) were given 23 mm or larger prostheses; subgroup BI (n = 147) underwent isolated AVR and subgroup BII (n = 77) underwent AVR with concomitant cardiac procedures. RESULTS: Hospital mortality was group A 7.3% versus group B 4.9%. Cumulative survival after six years was 83.7% in AI and 76.9% in AII versus 72.1% in BI and 77.4% in BII. There were no significant statistical differences between the subgroups concerning cardiac mortality. Thromboembolic events occurred with a linearized rate of 1.41%/pty in group A versus 1.03%/pty in group B, the incidence of anticoagulant-related major hemorrhage was 1.41%/pty in group A versus 1.20%/pty in group B and that of periprosthetic leakage 1.69%/pty in group A versus 1.89%/pty in group B. CONCLUSION: Our results demonstrate that this bileaflet prosthesis is highly efficient in patients with small aortic roots undergoing AVR with or without associated procedures.

[Total cavo-pulmonary connection as a therapeutic principle in anatomical and functional univentricular heart]. / Die totale cavo-pulmonale Konnektion als therapeutisches Prinzip bei anatomisch und funktionell univentrikulären Herzen.

The original Fontan operation was employed for patients with tricuspid atresia, but its application has been extended to a broad spectrum of congenital cardiac defects with a functional or anatomical single ventricle. From 1989 to 1995, 35 patients (23 males, 12 females) underwent a modified Fontan procedure; their age ranged from 14 months to 15 years (mean 5.1 a). Indications for operation were the following: D(S)ILV = 16, TA = 9, MA = 3, TGA with straddling AV-valve = 2, DORV = 4 and criss-cross heart = 1. The same surgical technique was utilized in all patients with redirection of the systemic venous return by means of a bidirectional cavopulmonary anastomosis and an intraatrial baffle, adaptable to all the various forms of underlying anatomy. Associated anomalies such as dextrocardia, coarctation, anomalous systemic or pulmonary venous return, subaortic stenosis and situs anomalies were present in 26%, 9%, 26%, 9%, and 20%, respectively. 12 patients were presumed to be at high risk and underwent a two-stage procedure (n = 7 bidirectional Glenn preceding the definitive repair and n = 5 a fenestration of the intraatrial baffle). Risk factors in our group of patients were: age under 2 years, abnormal systemic venous drainage, stenotic pulmonary arteries, PVR over 2 Wood units, mPAP over 15 mmHg, AV-valve incompetence, subaortic obstruction and ventricular dysfunction. Two patients had failure of the total cavo-pulmonary connection necessitating the take-down to a bidirectional Glenn anastomosis in the early postoperative period, with one death. Hospital mortality was 24% (n = 8). One child did not survive complications following the fenestration closure 4 months postoperatively.(ABSTRACT TRUNCATED AT 250 WORDS)

Preoperative myocardial cell damage in patients with unstable angina undergoing coronary artery bypass graft surgery.

BACKGROUND: Troponin-T is one of the contractile proteins of the myocardium. Its release into the circulation indicates various degrees of myocardial cell damage. Troponin-T may be measured in serum with a recently developed enzyme immunoassay. This immunoassay was used to evaluate the preoperative myocardial cell damage in patients with stable and unstable angina undergoing elective coronary artery bypass graft surgery, and it was compared with conventional assays of creatine kinase (CK) MB isoenzyme activity and mass. METHODS: Twenty-one patients with unstable angina and 31 with stable angina were studied. Troponin-T, CK-MB activity, and CK-MB mass were measured 24 h before anesthesia and surgery, immediately before induction of anesthesia, before and after cardiopulmonary bypass, at the end of surgery, and 24 h afterward. RESULTS: In 90% (19 of 21) of the patients with unstable angina, troponin-T was increased 24 h before anesthesia (median 0.33 microgram/l, range 0.15-5.2 micrograms/l), whereas only 3% (1 of 31) of the patients with stable angina had increased values (median 0.0 microgram/l, range 0.0-0.53 microgram/l). The difference was statistically significant (P < 0.001). The same profile was found in patients with and without unstable angina immediately before induction of anesthesia (86% [18 of 21] and 0%, respectively) and before cardiopulmonary bypass (62% [13 of 21] and 0%, respectively). In contrast to troponin-T, CK-MB activity was increased in only 0-14% of patients with unstable angina, and CK-MB mass was increased in only 9-24%. After bypass troponin-T increased in both groups (P < 0.01), but there was no longer a statistically significant difference between the groups. Twelve percent (4 of 31) of the patients in the stable angina group and 28% (6 of 21) in the unstable group had major cardiac events (P not significant). CONCLUSIONS: The study data suggest that many patients with unstable angina undergoing elective coronary artery bypass graft surgery have already increased troponin-T levels preoperatively, although conventional biochemical markers such as CK-MB activity and mass are at a normal range. Increased troponin-T and normal CK-MB concentrations may reflect some degree of ischemic myocardial cell damage. Because of the small number of patients in the study, the influence of preoperative myocardial injury on perioperative outcome could not be clarified.

Aortic dissection due to discontinuation of beta-blocker therapy.

beta-Blockers are known to protect a vulnerable aorta from acute dissection, as well as reducing the risk of recurrent dissection. This case presentation reports the history of a 60-year-old male suffering from acute aortic dissection following discontinuation of beta-blocker therapy. The patient has shown arterial hypertension for about 20 years treated solely by beta-blockers. Two days after stopping the use of metoprolol, a nonselective beta 1-blocker without ISA, the patient developed severe chest pain during exercise. Diagnosis of type I-aortic dissection according to DeBakey was achieved by transthoracal echocardiography and computed tomography. Successful surgery by replacement of the ascending aorta was performed about 1 h following admission to the intensive care unit. During the procedure, tamponade of the left ventricle occurred followed by cardiogenic shock. Postoperative management was complicated by prolonged respiratory therapy and acute gastrointestinal bleeding; 1-year follow-up showed no evidence of disease. Thus, in this case acute dissection may be the consequence of discontinuing the use of metoprolol, possibly due to uncontrolled hypertension or specific response to the beta-blocker.

Twenty-four years' implant duration of the aortic Starr-Edwards Silastic ball prosthesis: a valve of the past?

Six years after the first aortic valve replacement with the Starr-Edwards Silastic ball prosthesis at Oregon Health Sciences University, the model 1260 was implanted in a 44-year-old patient at our department. During 24 years no signs of dysfunction, thromboembolism, thrombosis, periprosthetic leaks or hemolysis were observed. Material test showed no signs of fatigue. The dimension of the Silastic poppet was found to be one millimeter less than the original specifications of these poppets and there were some lipid infiltrations. Functionally the poppet was found to be nonvariant. Histologic findings detected focal hyalinization and giant cells without signs of acute inflammation or ulceration. With regard to its reliability and durability, the Starr-Edwards valve prosthesis should not be viewed with disfavor.