Electrographic diagnosis of perforation of the heart by pacing catheter electrode

Pacemaker lead perforation of the right ventricle associated with Moraxella phenylpyruvica infection in a dog

CASE DESCRIPTION

A 13-year-old neutered male Border Collie was presented with acute onset syncope, weakness and anorexia 10 months after transvenous pacemaker implantation. The patient was laterally recumbent, bradycardic (36 beats/min) and febrile (40.7°C) on presentation. An electrocardiogram (ECG) revealed recurrence of third-degree atrioventricular block with a ventricular escape rhythm. Fluoroscopy identified migration of the pacemaker tip through the apex of the right ventricle. Echocardiography failed to reveal any evidence of pericardial effusion or cardiac tamponade. Full postmortem was performed after euthanasia. The pacemaker lead had perforated the apex of the right ventricle and lodged in the right pleural space. Culture of blood (taken antemortem), pericardial sac, right ventricular wall (surrounding pacemaker lead), pacemaker lead tip and pericardial fluid revealed a pure growth of Moraxella phenylpyruvica.

CONCLUSION

Bacteraemia associated with M. phenylpyruvica has never been reported in the dog, but sporadic cases are reported in humans. Infection could have resulted from either pre-existing myocarditis or opportunistic infection and bacteraemia post pacemaker implantation. Evaluation of the pacemaker function at regular intervals would allow early detection of poor pacemaker-to-myocardium contact, which would prompt further investigation of pacemaker lead abnormalities such as perforation.

Late cardiac perforation by a passive-fixation permanent pacemaker lead in a dog

CASE DESCRIPTION

A 12-year-old Miniature Dachshund with a history of permanent endocardial pacemaker implantation performed 7 weeks previously was admitted for routine dental prophylaxis.

CLINICAL FINDINGS

Preanesthetic ECG revealed normal ventricular capture. Thoracic radiographic findings included caudomedial displacement of the endocardial pacemaker lead. Echocardiography revealed moderate chronic degenerative valve disease with moderate left atrial and ventricular dilation. After induction of anesthesia, loss of ventricular capture was detected. The dog recovered from anesthesia and had improved ventricular capture. The following day, surgical exposure of the cardiac apex revealed perforation of the right ventricular apex by the passive-fixation pacemaker lead.

TREATMENT AND OUTCOME

A permanent epicardial pacemaker was implanted through a transxiphoid approach. Appropriate ventricular capture and sensing were achieved. The dog recovered without complications. Approximately 2 months later, the dog developed sudden respiratory distress at home and was euthanized.

CLINICAL RELEVANCE

In dogs with permanent pacemakers and loss of ventricular capture, differential diagnoses should include cardiac perforation. If evidence of perforation of the pacemaker lead is found, replacement of the endocardial pacemaker lead with an epicardial pacemaker lead is warranted.

Perforation of the right ventricle by transvenous defibrillator leads: prevention and treatment

A series of 78 consecutive implants of the transvene PCD (Medtronic, Inc.) defibrillator system is presented and the occurrence of right ventricular perforation in 4 patients reported (5.2%). Diagnosis of perforation is made using four signs: (1) decrease in arterial blood pressure without any other explanation; (2) decrease in pulsatility of the cardiac silhouette as monitored by fluoroscopy; (3) increased size of the cardiac silhouette; and (4) abnormal position of the transvenous lead too far out toward the left ventricle along the pericardial outline. Perforation causes rapid and dramatic cardiac tamponade due to the large diameter and stiffness of the coil carrier lead. Immediate drainage of the hemopericardium must be carried out using the transxiphoid approach. The use of a thin blue-coded lead stylet (0.014-inch gauge) is recommended over the stiffer maroon-coded stylet. Since treatment must be carried out immediately, it is advised that a surgeon either perform, assist, or be immediately available whenever one of these systems is implanted.

Pacemaker electrode perforation of the myocardium: an unusual etiology for recurrent abdominal pain

A 79-year-old man with a permanent pacemaker presented on five separate occasions to the emergency department with recurrent episodes of crampy abdominal pain. Extensive radiographic studies and repetitive labwork were nondiagnostic. Shortly after hospital admission on the fifth visit he experienced cardiac arrest and was successfully resuscitated. Poor pacemaker capture and paced clonic contractions of the diaphragm and abdominal wall were noted, suggesting myocardial perforation by the pacemaker electrode. A new lead and pulse generator were implanted and the patient was discharged without further abdominal discomfort. Implications of pacemaker electrode perforation of the myocardium are discussed.

Two-dimensional echocardiographic localization of a malpositioned pacing catheter

The precise intracardiac localization of transvenous pacing catheter electrodes is sometimes difficult yet crucial to patient management. We describe a patient in whom standard indirect studies failed to locate a malpositioned pacing catheter. Two-dimensional (2-D) echocardiographic examination revealed its entire aberrant course, from the right atrium, across the interatrial septum, through the mitral valve and on to the apex of the left ventricle. The value of this technique is reviewed.

Real-time, two-dimensional echocardiographic features of pacemaker perforation

Five patients (four adults and one child) with clinically suspected myocardial perforation by temporary transvenous pacemakers were studied by real-time, two-dimensional echocardiography. In three patients, the catheters were visualized passing through the right ventricular apical wall with the tip located outside the cardiac border. In one patient the catheter perforated the atrioventricular septum and entered the left ventricle with the tip lodged against the posterior wall. In another patient, the catheter had partially penetrated the ventricular septum near the apex. Pericardial effusion was observed in two patients, in one of whom it was localized to the site of perforation. No patient had evidence of cardiac tamponade. In four patients, the catheters were withdrawn under echocardiographic visualization and the catheter tips could be seen moving from the abnormal locations back into the right-heart chambers. Perforation was verified at autopsy in two patients, including one in whom the catheter was not withdrawn. Real-time, two-dimensional echocardiography appears to be valuable in the diagnosis of pacemaker perforation.

Transvenous magnetic tip lead system for permanent pacing of the heart. A preliminary report

An electrode for transvenous permanent ventricular pacing equipped with a supermagnet was implanted in six dogs in the apex of the right ventricle for several weeks. As no signs of myocardial perforation occurred, the device which consists of the magnetic tip lead and an external supermagnet applied to the precordial region of the chest wall was implanted in 14 patients. The lead was introduced through the right cephalic vein in 12 patients and through the right external jugular vein in the remaining 2 patients. Threshold values were measured twice a day in 12 patients who received a Siemens-Elema Vario pacemaker 629. The average peak threshold was reached on the 11th day after implantation. No pacing failure or other signs of acute dislodgement of leads occurred during the first 30 days.

Intracardiac electrocardiography during permanent pacemaker implantation: predictors of cardiac perforation

Intracardiac electrograms from 50 successive patients undergoing permanent pacemaker implantation have been analyzed. There were 29 male and 21 female patients aged 14 to 93 years (mean age 68.4 years). The electrograms were obtained using methods that simulated the wave form that would be detected by unipolar cardiac pacemakers. Three types of electrographic patterns were identified: qR pattern with a q/R ratio of less than 1 (type I): QR pattern with a Q/R ratio between 1 and 4.4 (type II); and Qr pattern with a Q/r ratio between 12 and 15 (type III). A type I pattern was seen in 29 patients (58 percent), type II in 18 (36 percent) and type III in 3 patients (6 percent). The duration of the follow-up period ranged from 3 weeks to 20 months (mean 9.7 months); three patients were lost to follow-up study. There were four deaths apparently unrelated to the pacemaker. Recognizable problems (either pacing or sensing failure) occurred in one patient (6 percent) with a type II pattern, in two patients (66.7 percent) with a type III pattern and in no patient with a type I pattern. On the basis of these data it is suggested that at the time of pacemaker implantation, intracardiac electrograms with a type I pattern indicating good pacing thresholds and sensing should be sought. If type II wave forms occur with good pacing thresholds and sensing then the electrode could probably be left in position. The incidence of a type III pattern is rare; when it does occur it is greatly suggestive of myocardial perforation. When this pattern is seen, the pacemaker catheter must be repositioned.

Comparison of active and passive adhering leads for endocardial pacing

The frequency of lead failure requiring invasive correction in a total of 276 implants of four different transvenous leads (6907, continuous lead, IE-65-I, and MIP 2000) was observed during a one-and-one-half year period with a minimum of two months follow-up post-implant. Implants were on a successive sequential basis, randomly distributed between the two surgeons normally performing implants, and unselected for presumed ease or difficulty of the procedure. Failure rates with the 6907 and continuous leads were 7 of 76, or 9.2%; with the IE-65-I, 2 of 76, or 2.6%; and with the MIP 2000, 8 of 45, or 17.8%. The difference between the IE-65-I and the two conventional leads was significant at the 5% level, and between the IE-65-I and the group of the other three at the 1.6% level. The MIP 2000 was significantly different from the other three leads at the 2.7% level. Previous clinical experience with 849 implants with continuous and 6807 leads indicated that the overall data was similar to that obtained in the present evaluation. No significant differences in failure rates between surgeons and no measurable "practice effect" could be detected. It was concluded that the design of the lead is a major factor in the differing need for early secondary intervention.

Electrograms from the coronary sinus in acute myocardial infarction: implications for electrocardiographic guidance of pacing catheters

Intracardiac electrocardiography has been reported to be the most reliable of the techniques used for guiding placement of transvenous pacing catheters. When a catheter electrode is in contact with the right ventricular apical endocardium, the intracardiac electrogram demonstrates marked ST segment elevation and, usually, a very large S wave. The case presented indicates that both of these features of the intracardiac electrogram should be sought since ST segment elevation alone may represent epicardial recording of an acute myocardial infarction when the catheter electrode is in the coronary venous system.

The diagnosis of right ventricular perforation by an endocardial pacemaker electrode

The diagnosis of right ventricular perforation by an endocardial pacemaker electrode should be suspected when failure of pacing occurs without electrode displacement. Although a number of changes occur on the standard electrocardiogram (ECG), none of these are diagnostic. The intracardiac electrogram performed during electrode withdrawal is not only diagnostic of perforation but can also aid in electrode positioning. Two case reports highlight these changes in the intracardiac electrogram. The first case also illustrates that, with electrode perforation, the ability to sense the intrinsic intracardiac electrical activity may be retained.

Myocardial perforation by flexible Elema endocardial pacing catheters

Hurwitz, B. J., Zion, M. M., and Promund Obel, I. W. (1974).Thorax, 29, 678-684. Myocardial perforation by flexible Elema endocardial pacing catheters. Myocardial perforation as a complication of permanent endocardial pacing with flexible Elema catheters is described in nine patients. In eight patients pacing failed, but there were no other serious ill-effects. Diaphragmatic pacing occurred in five patients. Radiological evidence of movement, either posteriorly and/or laterally, of the electrode tip was detected in five patients. In only two of them was the electrode seen to be definitely extracardiac in position. A change in the pacing wave form aided the diagnosis in two patients. In a further two patients electrode tip electrocardiograms helped to confirm the diagnosis where, upon withdrawal of the perforating electrode, small Q waves disappeared, RS complexes enlarged, and the ST segments became more elevated, with deeply inverted T waves.

Withdrawal and repositioning of the electrode catheters was performed in seven patients. In one, a new catheter was inserted, and in another, where uninterrupted cardiac pacing was accompanied by intermittent diaphragmatic pacing, the pacing system was left unaltered. The follow-up is from six months to four and a half years with one late death apparently unrelated to pacing failure.