Endocardial ventricular pacing through a bioprosthetic tricuspid valve

A patient with bioprosthetic tricuspid valve was treated with ventricular endocardial pacing using a new delivery system consisting of a steerable catheter and a 4.1 F bipolar, fixed-screw, steroid eluting lead. The functioning of the lead and bioprosthetic tricuspid valve was excellent during the following year.     

Intercommissural Lead Placement into a Right Ventricular Coronary Sinus—Utility of Intracardiac Echo Guidance

Patients with congenital heart disease and prosthetic valves frequently present management dilemmas related to cardiac pacing and lead placement. Permanent pacing of the right ventricle across a bioprosthetic tricuspid valve presents discreet issues related to its potential for traumatic injury and subsequent prosthetic valve dysfunction. Coronary sinus (CS) lead placement is being used more frequently to avoid valvular dysfunction. We report an unusual case in which the CS ostium was located ventricular to the tricuspid prosthesis. Intracardiac echocardiography was used to position a CS lead between the commissures of the tricuspid prosthesis resulting in trivial regurgitation acutely and at 1‐year follow‐up. (PACE 2011; 34:e30–e32)     

ED identification of cardiac septal abscess using conduction block on ECG

A case of cardiac septal abscess in a patient with a porcine bioprosthetic aortic valve who gradually developed a complete atrioventricular block on successive electrocardiograms (ECG) is reported. Emergency physicians should consider endocarditis with septal abscess in a patient with a prosthetic heart valve who presents with fever and a new conduction defect on ECG.     

BLEEDING ANGIODYSPLASIA: SHOULD WE CONCENTRATE MORE ON THE AORTIC VALVE THAN ON THE BOWEL?

A case of bleeding from angiodysplasia in association with aortic stenosis is presented. The particular interest in this patient is that the bleeding ceased immediately after the insertion of a bioprosthetic valve and recurred when the valve restenosed. Furthermore, the bleeding again promptly resolved when the valve was exchanged for a metallic prosthesis despite long-term anticoagulation. The implications of these observations are discussed.     

Valve-in-valve implantations: is this the new standard for degenerated bioprostheses? Review of the literature

Transcatheter aortic valve implantation has established itself as an alternative treatment for patients with valvular disease. In the current context of increasing bioprosthetic valve implants and an ageing population with growing comorbidities, a less invasive approach to the treatment of bioprosthetic dysfunction would be an appealing alternative to the standard of care. Transcatheter valve-in-valve implantation could be an alternative for patients who are deemed to be a high surgical risk. The valve-in-valve procedure is a minimally invasive percutaneous procedure where a valve can be implanted directly within a failing bioprosthetic valve. This technique can be applied to dysfunctional aortic bioprosthetic valves and can also be used in the pulmonary and atrioventricular valve bioprosthesis. We review the current literature to assess whether this technique may be the new standard for degenerated bioposthesis.     

二尖瓣位生物瓣置换术后瓣膜毁损的临床特征及超声表现

目的探究二尖瓣位生物瓣膜置换术再次手术患者临床表现及超声心动图特征,为二尖瓣生物瓣膜毁损病因学诊断提供依据。方法回顾性分析24例经手术证实二尖瓣生物瓣膜置换术后,需再次手术患者的一般临床资料和超声心动图改变,总结患者心脏生物瓣膜毁损一般临床特征及超声表现。结果 24例患者中,中位年龄为66岁,男8例,女16例。24例中初次二尖瓣生物瓣置换术后出现生物瓣毁损再次手术原因:12例单纯性瓣膜关闭不全,4例瓣膜狭窄并关闭不全,3例瓣膜关闭不全合并瓣周漏,2例单纯性瓣膜狭窄,1例瓣膜关闭不全伴感染性心内膜炎,1例瓣膜狭窄伴附壁血栓,1例瓣膜关闭不全伴赘生物形成。结论二尖瓣位生物瓣置换术后行再次换瓣术间隔时间长短不一,本研究大部分病例生物瓣置换术后第8~9年之间出现瓣膜毁损需再次手术,时间短者大部与感染有关,时间长者大多与瓣膜老化有关。     

Transcatheter treatment of complex pulmonic and aortic valvular disease following failed Ross procedure

A 63‐year‐old man with congenital bicuspid aortic valve disease and complex surgical history (that includes a Ross procedure complicated by cardiac arrest requiring emergency coronary artery bypass graft surgery, multiple subsequent sternotomies to treat a failed pulmonic homograft and pseudoaneurysm repair of the left and right ventricular outflow tracts (LVOT/RVOT), bioprosthetic aortic valve replacement, and aortic valve endocarditis) presented with worsening heart failure symptoms secondary to bioprosthetic aortic valve failure and recurrent pulmonic valve stenosis successfully treated with transcatheter intervention.     

News in brief

There is a lack of consensus as to the ideal antithrombotic strategy after bioprosthetic aortic valve replacement. Herein, the authors review the literature on this topic and find that most of the evidence is comprised of small observational data, with a few prospective trials. The bulk of the evidence is in favor of no anticoagulation after bioprosthetic aortic valve replacement in patients at low risk of thromboembolism. Most studies suggest using only antiplatelet therapy with the exception of two studies that advocate anticoagulation. One study suggests that no antithrombotic therapy at all may be safe. One study evaluated the question mechanistically, showing no increased microembolic signals on transcranial Doppler in patients receiving aspirin compared to patients who were anticoagulated. Based on the evidence presented, the authors recommend using aspirin only after bioprosthetic aortic valve replacement in patients at low risk of thromboembolism.     

Increased cellular expression of matrix proteins that regulate mineralization is associated with calcification of native human and porcine xenograft bioprosthetic heart valves.

Dystrophic mineralization remains the leading cause of stenotic or regurgitant failure in native human and porcine bioprosthetic heart valves. We hypothesized that cellular expression of noncollagenous matrix proteins (osteopontin, osteocalcin, and osteonectin) that regulate skeletal mineralization may orchestrate valvular calcification. Porcine bioprosthetic heart valves and native human heart valves obtained during replacement surgery were analyzed for cells, matrix proteins that regulate mineralization, and vessels. Cell accumulation and calcification were correlated for both valve types (rho = 0.75, P = 0.01, native; rho = 0.42, P = 0.08, bioprosthetic). Osteopontin expression correlated with cell accumulation (rho = 0.58, P = 0.04) and calcification (rho = 0.52, P = 0.06) for bioprosthetic valves. Osteocalcin expression correlated with calcification (rho = 0.77, P = 0.04) and cell accumulation (rho = 0.69, P = 0.07) in native valves. Comparisons of calcified versus noncalcified native and bioprosthetic valves for averaged total matrix protein mRNA signal score revealed increased noncollagenous proteins mRNA levels in calcified valves (P = 0.07, group I vs. group II; P = 0.02, group III vs. group IV). When stratified according to positive versus negative mRNA signal status, both calcified bioprosthetic valves (P = 0.03) and calcified native valves (P = 0.01) were significantly more positive for noncollagenous proteins mRNA than their noncalcified counterparts. Local cell-associated expression of proteins regulating mineralization suggests a highly coordinated mechanism of bioprosthetic and native valve calcification analogous to physiologic bone mineralization. Modulation of cellular infiltration or cellular expression of matrix proteins that regulate mineralization, may offer an effective therapeutic approach to the prevention of valve failure secondary to calcification.     

Alternate pacing sites for patients with tricuspid valve prostheses

The objective of this study was to pace via a coronary vein to avoid interfering with the tricuspid valve prosthesis function. Pacing leads were inserted into the posterior cardiac vein in a 68-year-old woman (patient 1), and in the great cardiac vein and the right auricle in a 32-year-old woman (patient 2). In patient 1 the stimulation threshold was 1.8 V at implant and stabilized at 3.0 V at the 24-month follow-up. In patient 2 the ventricular pacing threshold was 1.2 V at implant and stabilized at 0.7 V at the 24-month follow-up. The cardiac output at rest increased 43% during atrioventricular synchronous pacing compared to ventricular pacing. Long-term stable ventricular pacing via the coronary venous system was obtained.     

Guidewire pacing during transcatheter aortic valve implantation in a patient with complex congenital heart disease

We present a case of temporary guidewire pacing in a patient with Fontan anatomy during transcatheter aortic valve implantation. Temporary pacing was successfully achieved utilizing this method without complications. There is an increasing population of patients with complex congenital heart disease and expanding variety of transcatheter interventions. Due to limitations in vascular access and surgical anatomies, guidewire pacing may have a wide array of potential applications in pediatrics and the congenital heart disease population.     

Lead Dislodgment of a Permanent Pacemaker Due to Removal of a Temporary Pacing Electrode

A 63-year-old male received a transvenous temporary pacemaker for bradyarrhythmia following mitral valve replacement and tricuspid valve annuloplasty. A transvenous permanent pacemaker was implanted the following day due to persistence of the bradyarrythmia and pacemaker dependency of the patient. Later the same day during removal of the temporary pacing electrode the permanent pacing lead was dislodged and had to be operatively repositioned. To avoid this complication, the position of pacemaker leads should be checked postoperatively with a frontal and lateral chest radiograph, and fluoroscopy should be used during removal of a temporary lead.     

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.     

Dual site coronary sinus pacing in a patient with an artificial tricuspid valve prosthesis

For safety reasons, two leads for left ventricular pacing were implanted in the coronary sinus of a pacemaker dependent patient with an artificial tricuspid valve prosthesis.     

Transvenous Left Atrial and Left Ventricular Pacing in Ebstein's Anomaly with Severe Interatrial Conduction Block

The implantation of permanent pacemakers in patients with congenital heart disease can be challenging. This report describes the complexity of pacemaker implantation in a patient with Ebstein's disease, tricuspid valve replacement, and right atrial abnormalities like severe intra- and interatrial conduction block that prevented dual chamber pacing from conventional sites. This case illustrates the promising possibility to circumvent the interatrial conduction block with single left atrial pacing instead of biatrial pacing which was not suitable here.     

Aortic valve replacement: technique and outcome with artificial heart valves and allografts

Prosthetic aortic valve replacement has become a highly effective surgical treatment for aortic valve stenosis and aortic valve incompetence. After a properly timed aortic valve replacement, age- and gender-related actuarial survival can be similar to those of a normal healthy population, if serious late valve-related complications do not occur. The perioperative risk of isolated aortic valve replacement approaches 1% to 2% mainly influenced by valve- and patient-related factors such as age, left ventricular function, New York Heart Association class, preoperative hemodynamic and time of operation. Despite a number of various mechanical, bioprosthetic and biological heart valve prostheses, aortic valve replacement remains a palliative surgical treatment. Life-long anticoagulation is required by patients with mechanical heart valve prostheses, and, degeneration and subsequent reoperation is inherent in all bioprosthetic devices. The availability of cryopreserved allograft is limited and the Ross-operation is a technically demanding procedure with a somewhat higher perioperative mortality. Perioperative morbidity after isolated aortic valve replacement is low. A fatal neurological event, the most dreaded complication after aortic valve replacement, is found in about 0.5% of patients. Post-operatively, left ventricular hypertrophy decreases and cardiac dysfunction, reflected by the left-ventricular ejection rate is reversed in most patients, associated with an excellent clinical outcome and an age- and sex-specific normal long-term survival. To offer the most appropriate valve substitute to the individual patient, the debate focus on the question of whether patients benefit from durable mechanical heart valves or a primary anticoagulation-free bioprosthesis. However, there is no difference found between the prostheses types with regard to serious valve related complications such as major thromboembolism and hemorrhage, fatal reoperation and valve-related mortality. The search for an ideal permanent substitute for the aortic valve continues. To date, proper indication, optimal timing of the operation and careful analysis of the late results may help to improve the long-term survival of patients with after isolated aortic valve replacement.     

Permanent Pacing in Ebstein's Anomaly

Patients with Ebstein's anomaly present unique challenges to permanent pacing due to anatomical variations and tricuspid valve replacement. We retrospectively reviewed our experience with permanent pacing in patients with Ebstein's anomaly between 1976 and 1993. We identified 401 patients with Ebstein's anomaly, of whom 15 (3.7%) required permanent pacing (1 of the 15 was implanted elsewhere). Of the 15, there were 8 females and 7 males (mean age 32 years [range 7-74]); the indications for pacing were AV block in 11 and sinus node dysfunction in 4. Eight patients were programmed with WI and seven with DDD. All VVI patients were paced epicardially. Two patients with DDD pacemakers had transvenous atrial and ventricular leads, 4 DDD patients had transvenous atrial leads and epicardial ventricular leads, and 1 patient had both epicardial and transvenous systems. Associated surgical procedures included tricuspid valve replacement in 14 of 15, atrial septal defect repair in 10 of 15, atrioplasty in 7 of 15, prior tricuspid annuloplasty in 4 of 15, pulmonary vein dilation in 1 of 15, and conduction system ablation in 2 of 15. Patients had a mean follow-up of 35 months (range 1-168 months). Complications requiring operative intervention occurred in four patients. One patient had displacement of a transvenous ventricular lead. A second patient had an epicardial lead failure. A third patient had a nonfunctioning atrial lead that displaced across the tricuspid valve, causing severe tricuspid regurgitation. The fourth patient had multiple epicardial and endocardial leads exit block with secondary diaphragmatic stimulation. Permanent pacemakers were required in 3.7% of patients with Ebstein's anomaly, with the indication being intrinsic conduction disease in the majority of patients. Ninety-three percent of patients required tricuspid valve replacement, suggesting more severe manifestation of Ebstein's anomaly. Twenty-seven percent had complications requiring surgical intervention. Thus, permanent pacing in patients with Ebstein's anomaly can be challenging and should be approached by an experienced physician. (PACE 1997;20[Pt. I]:1243-1246)     

False aneurysm of the mitral-aortic intervalvular fibrosa after uncomplicated aortic valve replacement.

False aneurysms of the mitral-aortic intervalvular fibrosa are rare and usually complicate aortic valve endocarditis. We report a case of a false aneurysm of the mitral-aortic intervalvular fibrosa after recent bioprosthetic aortic valve replacement in the absence of endocarditis.     

Permanent pacemaker lead entrapment: role of the transesophageal echocardiography

Numerous complications induced by pacemaker electrodes have been reported. Although mild tricuspid regurgitation is a well-documented complication of transvenous right ventricular pacemaker leads secondary to abnormal valve coaptation, severe tricuspid regurgitation resultingfrom perforation of the tricuspid valve itself is a rare complication. This case report details a patient with severe tricuspid regurgitation secondary to impingement of the tricuspid valve by a permanent pacing lead that was diagnosed by transesophageal echocardiography. Surgical repair was advocated because of symptomatic significant tricuspid regurgitation.     

Pacemaker Induced Mitral Regurgitation: An Alternative Form of Pacemaker Syndrome

A patient in atrial fibrillation was referred for mitral valve replacement due to severe mitral regurgitation. A cardiac pacemaker had previously been implanted. Cardiac catheterization demonstrated large V waves in the wedge pressure tracing during ventricular pacing, which were not present during native conduction. A left ventriculogram demonstrated severe mitral regurgitation during ventricular pacing, but not during native conduction. This patient, in atrial fibrillation, had severe mitral regurgitation induced by ventricular pacing and not by native conduction. Pacemaker syndrome may be caused by mitral regurgitation that is probably not secondary to AV dissociation, but rather the result of dyssyn-chronous ventricular contraction.