Amac: Bu calismada primer spontan pnomotoraks olgularindaki elektrokardiyografik (EKG) degisiklikler degerlendirildi. Calismaplani:Primer spontan pnomotoraksli toplam 48 hasta (42 erkek, 6 kadin; ort. yas: 29.7±12.5 yil; dagilim 15-58 yil) Kasim 2010 Kasim 2011 tarihleri arasinda prospektif olarak incelendi. Pnomotoraks alani Rhea metodu ile hesaplandi. Her hastaya en az iki kere standart 12 derivasyonlu EKG cekildi (pnomotoraks tanisindan sonra ve gogus tupu uygulamasindan once EKGpnomotoraks ve akcigerin yeniden ekspanse olmasi ve radyolojik olarak dogrulanmasindan sonra EKGre-ekspanse). P dalgasi olcumu, PR mesafesi, QRS mesafesi, QT intervali ve kalp hizi icin duzeltilmis QT araligi (QTc) hesaplandi. Ayrica kalp hizi (dakikada nabiz sayisi), aks deviasyonu olcumleri ve prekordial derivasyonlarda QRS amplitudleri (QRSV1-6) hesaplandi. Bul gu lar: Pnomotoraks hastalarin 29’unda (%60.4) sol, 19’unda (%39.6) sag hemitoraksta idi. Pnomotoraks alaninin ortalamasi %43.0±21.5 idi. En sik gorulen semptomlar, 34 hastada (%70.8) gogus agrisi, 14 hastada (%29.2) nefes darligi idi. Pnomotoraks suresi 30 hastada (%62.5) ≤24 saat iken, 18 hastada (%37.5) >24 saat idi. Tedavi oncesi ve tedavi sonrasi QT suresi, aks deviasyonu, kalp hizi, QRSV1, QRSV4, QRSV5 ve QRSV6 degerleri arasinda istatistiksel olarak anlamli bir fark saptandi (sirasi ile p=0.001, p=0.023, p=0.001, p=0.010, p=0.046, p=0.000, p=0.008). Uc hastada sag dal bloku, iki hastada ST yukselmesi ve bir hastada T dalgasi sivriligi olmak uzere toplam yedi hastada iliskili QRS anormallikleri saptandi. Sonuc:Calisma bulgularimiz hem sag hem de sol pnomotoraksin kadinlarda daha belirgin olmak uzere, aks degisikligine neden olabilecegini ve QRSV 4, 5 ve 6 derivasyonlarinda voltajin drenaj sonu arttigini gostermektedir. Ayrica pnomotoraks sag dal bloku ve ST degisikligi gibi ozellikli EKG degisikliklerine de yol acabilir. Anah tar soz cuk ler: Elektrokardiyografi, pnomotoraks; sag dal bloku. Background:This study aims to evaluate the electrocardiographic (ECG) changes in patients with primary spontaneous pneumothorax. Methods: A total of 48 patients (42 males, 6 females; mean age 29.7±12.5 years, range 15 to 58 years) with PSP were prospectively analyzed between November 2010 and November 2011. Pneumothorax size was calculated using the Rhea method. At least two standard 12-lead ECG were obtained for each patient (after the diagnosis of pneumothorax and prior to drain placement ECGpneumothorax, and after a complete re-expansion of the lung was achieved and confirmed radiologically ECGre-expanded). P wave measurement, PR distance, QRS distance, QT interval and QT interval corrected for heart rate (QTc) were calculated. Heart rate (bpm), axis deviation measurement and the QRS amplitudes (QRSV1-6) in precordial leads were calculated. Results:There were 29 cases (60.4%) of left-sided and 19 cases (39.6%) of right-sided pneumothorax. The mean relative volume of pneumothorax was 43.0±21.5%. The most common symptoms included chest pain in 34 patients (70.8%) and dyspnea in 14 patients (29.2%). The pneumothorax duration was ≤24 hours in 30 patients (62.5%) and >24 hours in 18 patients (37.5%). There was a statistically significant difference between before and after the treatment for QT duration, axis deviation, heart rate, QRSV1, QRSV4, QRSV5 and QRSV6 (respectively; p=0.001, p=0.023, p=0.001, p=0.010, p=0.046, p=0.000, p=0.008). A total of seven patients had relevant QRS abnormalities including incomplete right bundle branch block in three patients, ST elevation in two patients and T-wave pointedness in one patient. Conclusion:Our study results suggest that left and right lung pneumothorax may cause axis variation, which is more pronounced in women, and that voltage increases after drainage in QRSV 4, 5 and 6 leads. In addition, pneumothorax may lead to specific ECG variations such as right bundle branch block and ST variations.