Catheter induced cardiac arrhythmia is a well-known complication encountered during pulmonary artery or cardiac catheterization. Injury to the cardiac conducting system often involves the right bundle branch which in a patient with preexisting left bundle branch block can lead to fatal arrhythmia including asystole. Such a complication during central venous cannulation is rare as it usually does not enter the heart. The guide wire or the cannula itself can cause such an injury during central venous cannulation. The length of the guide wire, its rigidity, and lack of set guidelines for its insertion make it theoretically more prone to cause such an injury. We report a case of LBBB that went into transient complete heart block following guide wire insertion during a central venous cannulation procedure.
Central venous cannulation is indispensable in the management of severely ill patients. A number of complications are known to arise from injury to the vein and the neighboring structures. A right bundle branch injury is one of the complications that can occur during the guide wire insertion. This type of injury can go unrecognized but in the presence of a preexisting left bundle branch block (LBBB) it can be life-threatening. We present a case of transient complete heart block that was caused during a guide wire insertion in a patient with a preexisting LBBB and discuss the incidence of such a complication and possible ways to prevent it.
A 77-year-old woman was transferred to the intensive care unit (ICU) of our hospital with altered mental status that was thought to be secondary to carbon dioxide retention caused by aspiration pneumonia. In the ICU, she progressed into hemodynamic shock. A central venous cannulation was attempted via the right internal jugular vein. Before performing the central venous cannulation, her heart rate was averaging 70–80 beats per minute. Following the cannulation, her heart rate suddenly dropped to 20 beats per minute and the cardiac tracing on the monitor showed a complete heart block (CHB). A stat electrocardiogram (EKG) was obtained which confirmed complete heart block with an escape rhythm (Figure
EKG at admission showing the preexisting left bundle branch block.
EKG following the procedure showing a complete heart block with an escape rhythm.
A right bundle branch block (RBBB) occurring during the passage of guide wire or a catheter into the heart has an incidence of 3–12% [
The superficial position of the right bundle branch in the right ventricle just below the tricuspid valve makes it more prone to injury from a foreign object [
When compared to pulmonary artery catheterization, a conduction block during central venous cannulation is rare; however unlike the pulmonary artery catheter insertion, a central venous cannulation is not always performed under cardiac monitoring. Moreover the guide wires used during central venous cannulation are more rigid making them theoretically more arrhythmogenic [
This case emphasizes the risk of a life-threatening complication that can occur during a guide wire insertion in a patient with preexisting LBBB. While the insertion of a pulmonary artery catheter is usually done in a monitored setting, central venous cannulations are mostly performed in a nonmonitored environment. Ideally a guide wire should have external markings indicating the length in centimeters for better guidance. Many institutions have replaced their central venous insertion kit with a guide wire marked at every 10 cm, but it is yet to be universally accepted. We suggest EKG monitoring for all patients prior to central venous cannulation. Additionally in patients with a preexisting LBBB, one should be very cautious during guide wire insertion, and if time permits, having a noninvasive transcutaneous pacemaker at bedside might be beneficial.
The authors declare that there is no conflict of interests regarding the submission of this paper.