A 75-year-old caucasian male patient with a diagnosis of dilative cardiomyopathy (echocardiographic biplane ejection fraction (EF) 23%) had sinus rhythm with left LBBB ECG (Figure a-b) (QRS with 136 ms) and a profound dyssynergic contraction profile. There was a history of Diabetes Typ II, hypertension and mild renal insufficiency (serum creatinine 1.63 mg/dl). Significant coronary artery disease had been excluded by angiography. Currently, he suffered from New York Heart Association (NYHA) III heart failure status and was admitted for implantation of a CRT – implantable cardioverter defibrillator (ICD). The operative procedure was unremarkable, although some difficulties advancing the right electrode into the right ventricle were reported. Chest X-ray after implantation (Figure a-b) excluded pneumothorax and electrodes appeared well placed. The patient was discharged one day after the procedure when the pacing ECG showed a narrowed QRS complex (Figure c-d) with optimal values of all three electrodes (Table ).\nOne month later on follow-up, the patient reported a marked improvement of his exercise capacity (NYHA II). Electrode values remained stable. An unscheduled echocardiogramm (Philips iE33) revealed a marked reduction of left ventricular dimensions with an improved monoplane ejection fraction (51%). However, through the mitral valve leaflets a thick electrode proceeded into the apex of the left ventricle. An additional transesophageal echocardiographic examination demonstrated the coronary sinus (CS) electrode in place (Figure a) but a malposition of the RV electrode passing the patent foramen ovale (PFO) via an Eustachian valve into the left ventricle (3 b-d).\nAfter studying the literature and informing the patient about possible consequences a revision procedure was performed. The RV electrode was easily removed from the left ventricle but could not be safely placed in the right heart without a sheat. A new electrode was advanced and fixed at the base of the right ventricle. Postprocedure chest x-ray (Figure c-d), ECG (Figure e-f), and measurements (Table ) all documented good results. This time a postprocedure echocardiogramm showed an intact mitral valve, persistent good left performance, and the RV electrode within the right heart.\nThis was a clinical study and no experimental work. No ethical committee had to be involved. Everything happened in the compliance with the Helsinki Declaration.
A 71-year-old female patient who was diagnosed as “rheumatic valvular heart disease, mitral stenosis and insufficiency” underwent mitral valve replacement in our thoracic surgery department two years ago. After the operation, amiodarone (0.2 mg bid) was administrated to the patient for a long time because of paroxysmal atrial fibrillation. Four days before admission, she suffered from dizziness without syncope or amaurosis, and then came to our emergency room. Electrocardiogram (ECG) indicated atrial fibrillation with slow ventricular rates (37–38/min). Cardiac ultrasound demonstrated postoperative state of mitral valve replacement, enlargement of left atria and mild reflux of pulmonary valve. A temporary pacemaker was implanted before admission. The patient was diagnosed as “rheumatic valvular heart disease, postoperative state of mitral valve replacement, atrial fibrillation with slow heart rate, the state of temporary pacemaker implantation, chronic heart failure (NYHA IIclass), and diabetes”.\nAmiodarone was discontinued after admission. One week later, we regulated the rhythm of patient’s temporary pacemaker to 30/min. ECG monitor suggested the occurrence of significant sinus bradycardia with atrio-ventricular junctional escape beat, and occasionally with pacing rhythm. Considering the degradation of patient’s sinuatrial node and atrioventricular node, a permanent dual-chamber pacemaker was prepared to be implanted. During the course of operation, patient suffered from chest distress, dyspnea, lung rales, and rapid atrial flutter in ECG, which suggested the aggravation of heart failure. After the treatment of oxygen, morphine (5 mg iv), and furosemide (20 mg iv), the patient was getting better. After operation, excess bleeding was found on the puncture site. Considering the severity of patient’s disease and poor operation endurance, a single-chamber pacemaker (PhilosIISR, BIOTRONIK Company) was chosen to take place of dual-chamber pacemaker after contacting with patient’s relatives. Parameters settings of the single-chamber pacemaker were demonstrated as follows: the threshold of ventricular pacing was 0.8 V (0.5mS); the amplitude of R wave was 30.1mv; and the electrode impedance was 856Ω.\nBoth pacemaker function and Holter indicated favorable behavior of the pacemaker after the operation, and stitches were taken out one week later. Nine days later, the reexamination of cardiac ultrasound demonstrated as follows: postoperative state of mitral valve replacement, normal artificial biological mitral valve, enlargement of left atria, mild reflux of aortic valve, mitral valve flow spectrum showing a single peak, and pacemaker in ascending aorta and left ventricle (Fig. ). Chest computed tomography (CT) scan indicated that the pacemaker electrode was put into aorta and left ventricular (Fig. ), which suggested that the pacemaker had been put into subclavian artery by mistake and the pacing electrode was implanted in the left heart.\nTraditional right ventricular apical pacing belongs to unphysiological pacing, while the most studied physiological pacing regions include right ventricular outflow tract (RVOT) and septum, which can improve patients’ heart function [, ]. However, various complications may appear during the course of RVOT and right ventricular septum pacing and increase the risk of operation, such as high threshold of pacing, difficult fixation and location of pacing leads, long-duration operation, easy dislocation, and even the cardiac perforation etc. [–]. Cardiac resynchronization therapy (CRT) has been widely applied in clinics to conduct left ventricular epicardial pacing via coronary sinus currently. However, it is difficult to conduct left ventricular endocardial pacing via the puncture site of atrial septum because of the occurrence of side-effects, such as high risk of thromboembolism, impact on the function of mitral valve, and myocardial damage caused by taking out the pacemaker. Therefore, we reported a case that pacemaker was implanted into left ventricle by mistake which made unnecessary troubles to our doctors.\nIn this case, patient’s diagnosis was definite. On October 6, 2014, a cardiac permanent pacemaker was implanted because the patient was suffering from atrial fibrillation and atrial flutter with sinus bradycardia (30-40/min). The reexamination of cardiac ultrasound demonstrated that the pacing leads were put into left heart, which suggested that pacing electrode was implanted into left ventricle via subclavian artery by mistake. The reasons included: 1) during the course of operation, patient’s heart function aggravated suddenly. Excess bleeding was observed after we performed a puncture on her subclavian artery by mistake. However, we regarded the excess bleeding and the increase of blood pressure as the results of the rise of central venous pressure caused by the aggravation of heart failure. Moreover, acute heart failure could result in hypoxia, which made troubles in recognizing whether the blood was from artery or vein; 2) after the pacing leads were implanted, the fluoroscopy should have been conducted in post-anterior view, 45-degree left anterior oblique view and 30-degree right anterior oblique view, respectively []. However, after the occurrence of chest distress, drugs were administrated to treat acute heart failure immediately, which also induce the operator to shorten the duration of operation. In addition, angiography has not been performed to confirm the location of pacing leads, and multiple body position fluoroscopy wasn’t conducted as well after the implantation of pacing electrode, while post-anterior view scanning during the course of operation couldn’t confirm the location of pacing electrode accurately (Fig. ); 3) it was easy to locate the passive electrode in traditional right ventricular apical pacing. In addition, the temporary pacing is implanted in the right ventricular apex generally, which is relatively helpful to locate the passive electrode in the right ventricular apex also. However, in our operation, the active electrode was used and prepared to implant into ventricular septum, which was difficult to locate. And it was hard to be located with the reference of the temporary pacemaker, which was normally positioned in the right ventricular apex. Therefore, we unfortunately mistook left ventricle for right ventricular low septum, and then the pacing electrode was implanted into left ventricle; 4) the electrocardiogram (ECG) after the pacemaker implantation is helpful in locating pacemaker. For example, the left bundle-branch block showed in ECG is common seen in right ventricular paced patients (Fig. ), while the right bundle-branch block in left ventricular paced patients. In this case, the patient suffered a sudden heart failure. The ECG suggested rapid atrial flutter without any pacemaker signal (Fig. ). Therefore, it was unable to evaluate the position of the lead through ECG.