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Pulmonary Varicosity Associated with Other Congenital Abnormalities
PULMONARY VARICOSITY relatively low pressures may fail to demonstrate the occurrence of such accidents. With hand injection under relatively low pressures, the contrast medium flows selectively through the more proximal orifices which are intraluminal. The tissue pressure during the hand injection is adequate to plug the distal holes so that the test injection shows no extravasation.' The NIH catheter is preferred to the Cournand catheter for angiographic work because it has a thinner wall and greater luminal diameter than a Cournand of the same French size, a closed tip and four spirally arranged side-holes, 1 to 2 ern proximal to the tip which permit discharge of the opaque medium in a manner that minimizes recoil of the catheter. The combination of a larger internal diameter and multiple side-holes permit discharge of the opaque medium over a wider area more rapidly than would injection through a single end-hole Cournand catheter. The difference in tip configuration between the NIH catheter and the Cournand catheter produces essentially no difference in the ability of these catheters to penetrate tissue. The major factor governing perforation of tissue by catheters appears to be the stiffness of the catheter material. Stiffness varies with the caliber and is inversely related to the degree of hydration of the catheter. The latter factor is markedly affected by the method of sterilization. Studies have shown that methods of sterilization which lead to dehydration of the catheter (dry heat, autoclaving with a vacuum drying cycle, and sterilization by ethylene oxide with a prolonged vacuum-gas evacuation cycle) lead to marked increases in catheter stiffness. Conversely, methods of sterilization that hydrate the catheter (boiling, cold sterilization in liquid germicides, autoclaving without a vacuum drying cycle) tend to markedly decrease the stiffness of the catheter, sometimes to the point where it cannot be effectively
manipulated." ACKNOWLEDGMENT: We wish to express appreciation to Miss Margie Hook for her excellent secretarial assistance and to Mr. Philip Alexander for his help in collecting the bibliographic material used in preparing this article. REFERENCES
1 Teramoto S: Accidental complications during performance of heart catheterization and cardtoangiography in three cases. jap J Thorac Surg 20:460-466, 1967 2 Davidsen H, Gudbjerg CE, Thomsen G: Complications of selective angiocardiography and percutaneous transarterial aortography. Acta Chir Scan Supp 283: 168-181, 1961 3 Doumanian 0, Amplatz K: Vascular jet collapse in selective angiocardiography. Amer J Roentgen 100:344-352, 1967 4 Escher, DJW, Shapiro H, Rubinstein BM: Perforation of the heart during cardiac catheterization and selective angiocardiography. Circulation 18:418-422, 1958 5 Lurie PR, Grajo MZ: Accidental cardiac puncture during right heart catheterization. Pediatrics 29:283-294, 1962 6 Braunwald E, Swan H: Cooperative study on cardiac catheterization. Circulation 37:5 (Supp 3) 36-38, 1968
CHEST, VOL. 62, NO.1, JULY, 1972
107
Pulmonary Varicosity Associated with Other Congenital Abnormalities * E. Papamichael, M.D.; D. lkkos, M.D.; K. Alkalais, M.D.; and J. }' an naco poulos
Varices of the pulmonary veins are rare. Only 29 cases have been reported up to now. We present another case of a pulmonary varix of the right lung associated with absence of the superior pulmonary vein, hypoplasia of the descending branch of the right pulmonary artery, congenital bronchiectasis of the middle and lower lobes, and inventration of the right diaphragm. A brief review of the literature is given. Because pulmonary varices radiologicaUy resemble mediastinal or pulmonary lesions, angiocardiography is indicated to avoid exploratory thoracotomies.
V
arices of the pulmonary veins are rare and in most cases clinically insignificant. Their importance lies in the radiologic appearance and their resemblance to coin lesion, pulmonary tuberculosis, bronchogenic carcinoma, mediastinal tumor, mediastinal lymphadenopathy and arteriovenous fistula. The recognition of pulmonary varices by angiocardiography is important if unnecessary exploratory thoracotomies are to be avoided. The first case of a pulmonary varix was described by Pucher' in 1843 as an incidental finding at necropsy in a newborn baby who died from intestinal hemorrhage and who presented multiple varices in other organs as well. Mouqin and associates- in 1951 and Gottesman and Weinstein" in 1959 demonstrated pulmonary varices in living persons for the first time by angiocardiography. Twenty nine cases, discovered at necropsy or proved by angiocardiography have been reported to date and of those only one patient! was operated upon. We report another rather unusual case of a varicosity of the right upper lobe associated with absence of the superior pulmonary vein, hypoplasia of the descending branch of the right pulmonary artery, congenital bronchiectasis of the middle and lower lobes and eventration of the right diaphragm. CASE REPORT
A 39-year-old man was admitted to the hospital because of recent severe hemoptysis. He had a history of three other severe hemoptyses in the last two years. He had no other symptoms and reported that, besides the hemoptyses, he had always been healthy and working. His chest x-ray film presented a pseudocavity with thick wall at the base of the right lung and an eventration of the right diaphragm (Fig 1). On the basis of tomography a diagnosis of an arteriovenous fistula was suspected and angiocardiography was carried out. The results of catheterization of the right heart chamber and pulmonary artery showed normal findings. Angiocardiography which followed demonstrated hypoplasia of ·From the Thoracic Surgical Clinic, the Cardiovascular and Pathology Laboratories of the Piraeus General Hospital "Queen Frederica," Piraeus, Greece. Reprint requests: Dr. Papamichael, 72 Vasilissis Sophias Av., Piraeus, Greece
108
FIGURE 1. Chest x-ray film showing dilated vessels and eventration of the diaphragm. the descending branch of the right pulmonary artery. A large varix of the pulmonary vein was identified on posteroanterior and lateral angiograms (Fig 2). Bronchography showed a stenosis of the intermediate bronchus and bronchiectasis with collapse of the middle and lower lobes. Tomography and bronchography of the left lung showed nothing abnonnaI. Because of the repeated severe hemoptyses, which were attributed to the presence of bronchiectasis, we operated upon the patient with the intention of resecting the bronchiectatic lobes. At operation on November 12, 1969, there was much
PAPAMICHAEL ET AL fibrosis and it was difficult to dissect the components of the hilum of the right lung. The pericardium was widely opened. The right superior vein was absent and there was only one pulmonary vein at the site of the right inferior vein. The only solution possible was to carry out a right pneumonectomy. The sole vein of the right lung and the artery were ligated intrapericardially. We could not dissect the main bronchus because of extensive fibrosis. Bleeding from the dilated bronchial vessels was a problem and the life of the patient was in danger. So we dissected the right upper lobe bronchus which was cut and closed with linen thread. The same was done for the intermediate bronchus; thus we unwillingly left a long bronchial stump. The patient left the hospital a month postoperation but he was readmitted two weeks later because of signs of bronchopleural fistula. Some clotted blood was removed at multiple right chest punctures. Cultures of the blood clots gave negative results. Antibiotics were given and he left the hospital 15 days later. Since then, he has been in good condition. The pathology of the specimen showed that the middle and lower lobes were collapsed and their bronchi dilated. There was only one pulmonary vein posteriorly. The diameter of the stem of the vein was 0.8 em, and at a distance about 1.5 cm from its ligation it was dilated to a diameter of 2 ern. A second dilated portion distal to the first one had a diameter of 3 ern. From the inside of these ectasias numerous openings were noted, corresponding to branches draining into the varix. Microscopically the wall of the nondilated part of the vein was thick, whereas the wall of the dilated part was extremely thin. The muscular layer was replaced by fibrous tissue. DISCUSSION
Varicosities of the pulmonary veins are more frequent in the right lung and especially in the upper lobe (ie 18 in the right upper lobe, eight in the right lower lobe, one in the left upper lobe, one in the left lower lobe and one in both lower lobes).' There is no difference according to sex incidence (14 males, 15 females). The youngest patient was a newborn baby and the oldest, 62 years old. Most of the cases were described in patients between the ages of 30 to 45. A varix of the pulmonary vein usually does not give any symptoms. It is an accidental finding in a chest x-ray examination. Its radiologic appearance might lead to an erroneous diagnosis of a pulmonary or mediastinal lesion as mentioned above. The vascular nature of the lesion is suspected from a plain chest x-ray film and is verified by tomography. From tomography one might suspect an arteriovenous fistula, even in absence of characteristic symptoms. The exact diagnosis is made only by angiocardiography. If accurate diagnosis is not made, unnecessary exploratory thoracotomy may be carried OUt. B•7
FIGURE 2. Posteroanterior angiogram showing the varix of the pulmonary vein.
Varices of the pulmonary veins are usually single and their etiology unknown. The fact that they also appear in young people, and the existence in some cases of other congenital abnormalities as well, gives the impression that their origin is congenital. Three cases were associated with congenital abnormalities. In one case there was a patent ductus arteriosus," in another a ventricular septal defect with origin of both great vessels from the
CHEST, VOL. 62, NO.1, JULY, 1972
109
HAZARD OF TWO FUNCTIONING PACEMAKERS right ventricle? and in the third a coarctation of the aorta." In our case there were multiple congenital anomalies as stated above. Pulmonary venous hypertension as an etiologic factor is greatly suspected. In Gottesman and Weinstein's" case the varix demonstrated no change ten years after mitral commissurotomy. Hipona and jamshidi'" reported that in one patient the pulmonary varix enlarged in seven years with progression of mitral insufficiency and then disappeared radiologically two years after prosthetic replacement of the mitral valve. Two of the cases described by Bryk and Levin; were associated with pulmonary venous hypertension in rheumatic heart disease. Pulmonary venous hypertension was present in two cases associated with congenital cardiovascular abnormalities.s-" Only one case was treated by Iingulectomy because it was thought that the varix was responsible for repeated pneumonias.' The pathologic examination of the varix did not show any signs in favor of this suspicion. We operated upon our patient because of repeated severe hemoptyses which were probably due to bronchiectasis. Our intention was to resect only the two bronchiectatic lobes but pneumonectomy was inevitable since the single vein of the lung was ligated. The pathologic examination of the varix did not show any signs of rupture. The vein's wall was thick and fibrosed, but at the most dilated part the wall was extremely thin, which proved that under certain circumstances the varix could rupture. Though three patients died because of rupture of the varis l1 - 13 (one into the pleural cavity and two into the bronchial tree) it seems that surgery is not indicated for most of the cases. Until our experience on pulmonary varices is increased, it is generally agreed that these patients should be under observation and surgery should be carried out only if the varix shows any change in size or shape. REFERENCES
1 Puchet: quoted by Gimes B, Horvath F: Uber die Varikositiit de Pulmonaivene. Fortschr Rontgenstr 87:545, 1958 2 Mouqin M, Hebrard H, Damasio R, et al: Varice du poumon diagnostiquee par I'angiocardiographie. Bull Soc med Hop Paris 67: 1091, 1951 3 Gottesman L, Weinstein A: Varicosity of the pulmonary veins: a case report and survey of the literature. Dis Chest 35:322, 1959 4 Hagen H, Heinz K: Varixknoten in Lingulast der Vena pulmonalis. Fortschr Hontgenstr 93: 151, 1960 5 Rizk G, Malhem R, Dagher I: Bilateral pulmonary varicosities associated with coarctation of the aorta. Thorax 25:97, 1970 6 Steinberg I: Pulmonary varices mistaken for pulmonary and hilar disease. Amer J Roentgenol 101:947, 1967 7 Bryk D, Levin EJ: Pulmonary varicosity. Radiology 85: 834, 1965 8 Vangsarkar AS, Kincaid OW, Weidman WH: Selective angiography in diagnosis of varicosity of the pulmonary veins. Amer Heart J 66:396, 1963 9 Redo FS, Engle MA, Holswade RG, et al: Operative correction of ventricular septal defect with origin of both
CHEST, VOL. 62, NO.1, JULY, 1972
10 11 12 13
great vessels from the right ventricle. J Thorac Cardiovase Surg 45:526, 1963 Hipona FA, Jamshidi A: Observation on the natural history of varicosity of pulmonary veins. Circulation 35: 471,1967 Klinck GH, Hunt HD: Pulmonary varix with spontaneous rupture and death. Arch Path 15;227, 1933 Neiman GH: Varix of the pulmonary vein. Amer J RoentgenoI32:608,1934 Perret L, Fortelius P: Ruptured aneurysm of the pulmonary vein. Acta Tuberc Scand 41:53,1962
Potential Hazard of Two Functioning Pacemakers* Lawrence Gould, M.D. and Robert F. Gomprecht, M.D.
A patient with the bradycardia-tachycardia syndrome received a permanent ventricular inhibited demand pacemaker as well as a standby temponry traosvenous pacemaker. When ventricular premature beats were seen, the temponry pacemaker was activated at 135 beats/min. Sinus bradycardia was now seen due to the inhibition of the permanent pacemaker by the pacing stimuH of the non-capturing temporary pacemaker.
T
he advent of internal implanted cardiac pacemakers has been a significant contribution to the management of heart block. However, complications related to improper pacemaker function are commonly seen with pacing systems. When the permanent pacemaker paces intermittently, a temporary transvenous pacing catheter may have to be inserted in order to avoid the symptoms of asystole. The simultaneous functioning of two cardiac pacemakers is theoretically objectionable since ventricular fibrillation can ensue. This can result from a pacemaker stimulus occurring during the vulner·From Misericordia-Fordham Hospitals, Bronx, New York.
Reprint requests; Dr. Gould, Misericordia Hospital, Bronx 10466
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FIGURE 1. Initial excellent functioning of ventricular demand pacemaker.
manipulated." ACKNOWLEDGMENT: We wish to express appreciation to Miss Margie Hook for her excellent secretarial assistance and to Mr. Philip Alexander for his help in collecting the bibliographic material used in preparing this article. REFERENCES
1 Teramoto S: Accidental complications during performance of heart catheterization and cardtoangiography in three cases. jap J Thorac Surg 20:460-466, 1967 2 Davidsen H, Gudbjerg CE, Thomsen G: Complications of selective angiocardiography and percutaneous transarterial aortography. Acta Chir Scan Supp 283: 168-181, 1961 3 Doumanian 0, Amplatz K: Vascular jet collapse in selective angiocardiography. Amer J Roentgen 100:344-352, 1967 4 Escher, DJW, Shapiro H, Rubinstein BM: Perforation of the heart during cardiac catheterization and selective angiocardiography. Circulation 18:418-422, 1958 5 Lurie PR, Grajo MZ: Accidental cardiac puncture during right heart catheterization. Pediatrics 29:283-294, 1962 6 Braunwald E, Swan H: Cooperative study on cardiac catheterization. Circulation 37:5 (Supp 3) 36-38, 1968
CHEST, VOL. 62, NO.1, JULY, 1972
107
Pulmonary Varicosity Associated with Other Congenital Abnormalities * E. Papamichael, M.D.; D. lkkos, M.D.; K. Alkalais, M.D.; and J. }' an naco poulos
Varices of the pulmonary veins are rare. Only 29 cases have been reported up to now. We present another case of a pulmonary varix of the right lung associated with absence of the superior pulmonary vein, hypoplasia of the descending branch of the right pulmonary artery, congenital bronchiectasis of the middle and lower lobes, and inventration of the right diaphragm. A brief review of the literature is given. Because pulmonary varices radiologicaUy resemble mediastinal or pulmonary lesions, angiocardiography is indicated to avoid exploratory thoracotomies.
V
arices of the pulmonary veins are rare and in most cases clinically insignificant. Their importance lies in the radiologic appearance and their resemblance to coin lesion, pulmonary tuberculosis, bronchogenic carcinoma, mediastinal tumor, mediastinal lymphadenopathy and arteriovenous fistula. The recognition of pulmonary varices by angiocardiography is important if unnecessary exploratory thoracotomies are to be avoided. The first case of a pulmonary varix was described by Pucher' in 1843 as an incidental finding at necropsy in a newborn baby who died from intestinal hemorrhage and who presented multiple varices in other organs as well. Mouqin and associates- in 1951 and Gottesman and Weinstein" in 1959 demonstrated pulmonary varices in living persons for the first time by angiocardiography. Twenty nine cases, discovered at necropsy or proved by angiocardiography have been reported to date and of those only one patient! was operated upon. We report another rather unusual case of a varicosity of the right upper lobe associated with absence of the superior pulmonary vein, hypoplasia of the descending branch of the right pulmonary artery, congenital bronchiectasis of the middle and lower lobes and eventration of the right diaphragm. CASE REPORT
A 39-year-old man was admitted to the hospital because of recent severe hemoptysis. He had a history of three other severe hemoptyses in the last two years. He had no other symptoms and reported that, besides the hemoptyses, he had always been healthy and working. His chest x-ray film presented a pseudocavity with thick wall at the base of the right lung and an eventration of the right diaphragm (Fig 1). On the basis of tomography a diagnosis of an arteriovenous fistula was suspected and angiocardiography was carried out. The results of catheterization of the right heart chamber and pulmonary artery showed normal findings. Angiocardiography which followed demonstrated hypoplasia of ·From the Thoracic Surgical Clinic, the Cardiovascular and Pathology Laboratories of the Piraeus General Hospital "Queen Frederica," Piraeus, Greece. Reprint requests: Dr. Papamichael, 72 Vasilissis Sophias Av., Piraeus, Greece
108
FIGURE 1. Chest x-ray film showing dilated vessels and eventration of the diaphragm. the descending branch of the right pulmonary artery. A large varix of the pulmonary vein was identified on posteroanterior and lateral angiograms (Fig 2). Bronchography showed a stenosis of the intermediate bronchus and bronchiectasis with collapse of the middle and lower lobes. Tomography and bronchography of the left lung showed nothing abnonnaI. Because of the repeated severe hemoptyses, which were attributed to the presence of bronchiectasis, we operated upon the patient with the intention of resecting the bronchiectatic lobes. At operation on November 12, 1969, there was much
PAPAMICHAEL ET AL fibrosis and it was difficult to dissect the components of the hilum of the right lung. The pericardium was widely opened. The right superior vein was absent and there was only one pulmonary vein at the site of the right inferior vein. The only solution possible was to carry out a right pneumonectomy. The sole vein of the right lung and the artery were ligated intrapericardially. We could not dissect the main bronchus because of extensive fibrosis. Bleeding from the dilated bronchial vessels was a problem and the life of the patient was in danger. So we dissected the right upper lobe bronchus which was cut and closed with linen thread. The same was done for the intermediate bronchus; thus we unwillingly left a long bronchial stump. The patient left the hospital a month postoperation but he was readmitted two weeks later because of signs of bronchopleural fistula. Some clotted blood was removed at multiple right chest punctures. Cultures of the blood clots gave negative results. Antibiotics were given and he left the hospital 15 days later. Since then, he has been in good condition. The pathology of the specimen showed that the middle and lower lobes were collapsed and their bronchi dilated. There was only one pulmonary vein posteriorly. The diameter of the stem of the vein was 0.8 em, and at a distance about 1.5 cm from its ligation it was dilated to a diameter of 2 ern. A second dilated portion distal to the first one had a diameter of 3 ern. From the inside of these ectasias numerous openings were noted, corresponding to branches draining into the varix. Microscopically the wall of the nondilated part of the vein was thick, whereas the wall of the dilated part was extremely thin. The muscular layer was replaced by fibrous tissue. DISCUSSION
Varicosities of the pulmonary veins are more frequent in the right lung and especially in the upper lobe (ie 18 in the right upper lobe, eight in the right lower lobe, one in the left upper lobe, one in the left lower lobe and one in both lower lobes).' There is no difference according to sex incidence (14 males, 15 females). The youngest patient was a newborn baby and the oldest, 62 years old. Most of the cases were described in patients between the ages of 30 to 45. A varix of the pulmonary vein usually does not give any symptoms. It is an accidental finding in a chest x-ray examination. Its radiologic appearance might lead to an erroneous diagnosis of a pulmonary or mediastinal lesion as mentioned above. The vascular nature of the lesion is suspected from a plain chest x-ray film and is verified by tomography. From tomography one might suspect an arteriovenous fistula, even in absence of characteristic symptoms. The exact diagnosis is made only by angiocardiography. If accurate diagnosis is not made, unnecessary exploratory thoracotomy may be carried OUt. B•7
FIGURE 2. Posteroanterior angiogram showing the varix of the pulmonary vein.
Varices of the pulmonary veins are usually single and their etiology unknown. The fact that they also appear in young people, and the existence in some cases of other congenital abnormalities as well, gives the impression that their origin is congenital. Three cases were associated with congenital abnormalities. In one case there was a patent ductus arteriosus," in another a ventricular septal defect with origin of both great vessels from the
CHEST, VOL. 62, NO.1, JULY, 1972
109
HAZARD OF TWO FUNCTIONING PACEMAKERS right ventricle? and in the third a coarctation of the aorta." In our case there were multiple congenital anomalies as stated above. Pulmonary venous hypertension as an etiologic factor is greatly suspected. In Gottesman and Weinstein's" case the varix demonstrated no change ten years after mitral commissurotomy. Hipona and jamshidi'" reported that in one patient the pulmonary varix enlarged in seven years with progression of mitral insufficiency and then disappeared radiologically two years after prosthetic replacement of the mitral valve. Two of the cases described by Bryk and Levin; were associated with pulmonary venous hypertension in rheumatic heart disease. Pulmonary venous hypertension was present in two cases associated with congenital cardiovascular abnormalities.s-" Only one case was treated by Iingulectomy because it was thought that the varix was responsible for repeated pneumonias.' The pathologic examination of the varix did not show any signs in favor of this suspicion. We operated upon our patient because of repeated severe hemoptyses which were probably due to bronchiectasis. Our intention was to resect only the two bronchiectatic lobes but pneumonectomy was inevitable since the single vein of the lung was ligated. The pathologic examination of the varix did not show any signs of rupture. The vein's wall was thick and fibrosed, but at the most dilated part the wall was extremely thin, which proved that under certain circumstances the varix could rupture. Though three patients died because of rupture of the varis l1 - 13 (one into the pleural cavity and two into the bronchial tree) it seems that surgery is not indicated for most of the cases. Until our experience on pulmonary varices is increased, it is generally agreed that these patients should be under observation and surgery should be carried out only if the varix shows any change in size or shape. REFERENCES
1 Puchet: quoted by Gimes B, Horvath F: Uber die Varikositiit de Pulmonaivene. Fortschr Rontgenstr 87:545, 1958 2 Mouqin M, Hebrard H, Damasio R, et al: Varice du poumon diagnostiquee par I'angiocardiographie. Bull Soc med Hop Paris 67: 1091, 1951 3 Gottesman L, Weinstein A: Varicosity of the pulmonary veins: a case report and survey of the literature. Dis Chest 35:322, 1959 4 Hagen H, Heinz K: Varixknoten in Lingulast der Vena pulmonalis. Fortschr Hontgenstr 93: 151, 1960 5 Rizk G, Malhem R, Dagher I: Bilateral pulmonary varicosities associated with coarctation of the aorta. Thorax 25:97, 1970 6 Steinberg I: Pulmonary varices mistaken for pulmonary and hilar disease. Amer J Roentgenol 101:947, 1967 7 Bryk D, Levin EJ: Pulmonary varicosity. Radiology 85: 834, 1965 8 Vangsarkar AS, Kincaid OW, Weidman WH: Selective angiography in diagnosis of varicosity of the pulmonary veins. Amer Heart J 66:396, 1963 9 Redo FS, Engle MA, Holswade RG, et al: Operative correction of ventricular septal defect with origin of both
CHEST, VOL. 62, NO.1, JULY, 1972
10 11 12 13
great vessels from the right ventricle. J Thorac Cardiovase Surg 45:526, 1963 Hipona FA, Jamshidi A: Observation on the natural history of varicosity of pulmonary veins. Circulation 35: 471,1967 Klinck GH, Hunt HD: Pulmonary varix with spontaneous rupture and death. Arch Path 15;227, 1933 Neiman GH: Varix of the pulmonary vein. Amer J RoentgenoI32:608,1934 Perret L, Fortelius P: Ruptured aneurysm of the pulmonary vein. Acta Tuberc Scand 41:53,1962
Potential Hazard of Two Functioning Pacemakers* Lawrence Gould, M.D. and Robert F. Gomprecht, M.D.
A patient with the bradycardia-tachycardia syndrome received a permanent ventricular inhibited demand pacemaker as well as a standby temponry traosvenous pacemaker. When ventricular premature beats were seen, the temponry pacemaker was activated at 135 beats/min. Sinus bradycardia was now seen due to the inhibition of the permanent pacemaker by the pacing stimuH of the non-capturing temporary pacemaker.
T
he advent of internal implanted cardiac pacemakers has been a significant contribution to the management of heart block. However, complications related to improper pacemaker function are commonly seen with pacing systems. When the permanent pacemaker paces intermittently, a temporary transvenous pacing catheter may have to be inserted in order to avoid the symptoms of asystole. The simultaneous functioning of two cardiac pacemakers is theoretically objectionable since ventricular fibrillation can ensue. This can result from a pacemaker stimulus occurring during the vulner·From Misericordia-Fordham Hospitals, Bronx, New York.
Reprint requests; Dr. Gould, Misericordia Hospital, Bronx 10466
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, .• _ ··4.
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.
-~
t-I;;o~~P:: -
n-iW 'N..lrJ"':t ...
.-'
:.... :
,
-
.. -:--~--
- ' T' -
,'n:~~~
~~:.: ,..... ~-;
Jt
i
-.,
_(~'/'j('-
·Ri~L~~:)~~
FIGURE 1. Initial excellent functioning of ventricular demand pacemaker.